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Employee Benefit Plans - Schedule of Components of Net Benefit (Gain) Cost (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Pension Plan
Schedule of Allocation of Plan Assets [Line Items]
Service Cost	$ 967	$ 1,270	$ 1,551
Interest Cost	4,635	4,280	4,270
Expected Return on Plan Assets	(6,748)	(6,322)	(5,865)
Amortization of Net Actuarial Loss (Gain)	50	153	658
Net Periodic Benefit (Gain) Cost	(1,096)	(619)	614
Other Benefits Plan
Schedule of Allocation of Plan Assets [Line Items]
Service Cost	340	320	391
Interest Cost	1,719	1,313	1,608
Expected Return on Plan Assets	(3,712)	(3,384)	(3,082)
Amortization of Net Actuarial Loss (Gain)	(613)	(1,098)	(191)
Net Periodic Benefit (Gain) Cost	$ (2,266)	$ (2,849)	$ (1,274)

Capitalization - Schedule of Long-Term Debt (Details) $ in Millions	Dec. 31, 2025 USD ($)
Equity [Abstract]
2026	$ 7.9
2027	7.5
2028	7.2
2029	6.7
2030	5.8
Thereafter	$ 350.8

Employee Benefit Plans (Tables)

12 Months Ended

Dec. 31, 2025

Retirement Benefits [Abstract]

Schedule of Employee Benefit Plans Recognized in Balance Sheet

The tables below set forth information relating to the Company’s Pension Plan and Other Benefits Plan for 2025 and 2024.


	(In Thousands)
	Pension Plan				Other Benefits Plan
	Years Ended December 31,
	2025		2024		2025		2024
Change in Projected Benefit Obligation:
Beginning Balance	$	87,501	$	91,853	$	28,201	$	28,000
Service Cost	967		1,270		340		320
Interest Cost	4,635		4,280		1,719		1,313
Actuarial (Gain) Loss	1,026		(5,478)		2,867		(486)
Benefits Paid	(5,079)		(4,424)		(1,102)		(946)
Ending Balance	$	89,050	$	87,501	$	32,025	$	28,201

Schedule of Change in Fair Value of Plan Assets


	(In Thousands)
	Pension Plan				Other Benefits Plan
	Years Ended December 31,
	2025		2024		2025		2024
Change in Fair Value of Plan Assets:
Beginning Balance	$	98,648	$	92,346	$	53,027	$	48,352
Actual Return on Plan Assets	9,566		7,976		7,473		4,675
Employer Contributions	886		2,750		1,102		946
Benefits Paid	(5,079)		(4,424)		(1,102)		(946)
Ending Balance	$	104,021	$	98,648	$	60,500	$	53,027

Funded Status	$	14,971	$	11,147	$	28,474	$	24,826

Schedule of Employee Benefit Plans Recognized in Balance Sheet


	(In Thousands)
	Pension Plan				Other Benefits Plan
	As of December 31,
	2025		2024		2025		2024
Amounts Recognized in the Consolidated
Balance Sheets consist of:
Current Liability	$	883	$	883	$	—	$	—
Noncurrent Asset	(15,854)		(12,030)		(28,474)		(24,826)
Net Asset Recognized	$	(14,971)	$	(11,147)	$	(28,474)	$	(24,826)

Schedule of Components of Net Benefit Cost


	(In Thousands)
	Pension Plan						Other Benefits Plan
	Years Ended December 31,
	2025		2024		2023		2025		2024		2023
Components of Net Periodic Benefit (Gain) Cost
Service Cost	$	967	$	1,270	$	1,551	$	340	$	320	$	391
Interest Cost	4,635		4,280		4,270		1,719		1,313		1,608
Expected Return on Plan Assets	(6,748)		(6,322)		(5,865)		(3,712)		(3,384)		(3,082)
Amortization of Net Actuarial Loss (Gain)	50		153		658		(613)		(1,098)		(191)
Net Periodic Benefit (Gain) Cost*	$	(1,096)	$	(619)	$	614	$	(2,266)	$	(2,849)	$	(1,274)

*Service cost is included in Operations and Maintenance expense on the consolidated statements of income; all other amounts are included in Other Income, net.

Schedule of Regulatory Assets into Net Periodic Benefit Cost

Amounts that are expected to be amortized from Regulatory Assets into Net Periodic Benefit Cost in 2025 are as follows:


	(In Thousands)
	Pension Plan		Other Benefits Plan
Actuarial Loss (Gain)	$	74	$	(1,071)

Schedule of Discount and Compensation Rates

The discount rate and compensation increase rate for determining our postretirement benefit plans’ benefit obligations and costs as of and for the years ended December 31, 2025, 2024 and 2023, respectively, are as follows:


	Pension Plan						Other Benefits Plan
	2025		2024		2023		2025		2024		2023
Weighted Average Assumptions:
Expected Return on Plan Assets for:
Benefit Cost	7.00	%	7.00	%	7.00	%	7.00	%	7.00	%	7.00	%
Discount Rate for:
Benefit Obligation	5.39	%	5.47	%	4.79	%	5.49	%	5.49	%	4.79	%
Benefit Cost	5.47	%	4.79	%	4.98	%	5.49	%	4.79	%	4.98	%
Compensation Increase for:
Benefit Obligation	3.00	%	3.00	%	3.00	%	3.00	%	3.00	%	3.00	%
Benefit Cost	3.00	%	3.00	%	3.00	%	3.00	%	3.00	%	3.00	%

Schedule of Effect of One-Percentage Point Change in Assumed Health Care Cost Trend Rates

A one-percentage point change in assumed healthcare cost trend rates would have the following effects on the Other Benefits Plan:


	(In Thousands)
	1 Percentage Point
	Increase		Decrease
Effect on Current Year Service and Interest Costs	$	295	$	(239)
Effect on Projected Benefit Obligation	$	4,199	$	(3,434)

Schedule of Expected Benefit Payments

The following benefit payments, which reflect expected future service, are expected to be paid:


	(In Thousands)
Year	Pension Plan		Other Benefits Plan
2026	$	5,446	$	1,355
2027	5,466		1,427
2028	5,588		1,491
2029	5,586		1,593
2030	5,691		1,654
2030-2034	30,481		9,549
Totals	$	58,258	$	17,070

Schedule of Allocation of Plan Assets

The allocation of plan assets at December 31, 2025 and 2024 by asset category is as follows:


	Pension Plan						Other Benefits Plan
Asset Category	2025		2024		Target		2025		2024		Target
Equity Securities	51.9	%	31.8	%	30	%	68.0	%	65.2	%	65	%
Debt Securities	47.5	%	67.9	%	68	%	30.0	%	33.0	%	33	%
Cash	0.6	%	0.3	%	2	%	2.0	%	1.8	%	2	%
Total	100.0	%	100.0	%			100.0	%	100.0	%

Schedule of Fair Value of Plan Assets

The following tables present Middlesex’s Pension Plan assets measured and recorded at fair value within the fair value hierarchy:


	(In Thousands)
	As of December 31, 2025
	Level 1		Level 2		Level 3		Total
Money Market Funds	$	637	$	—	$	—	$	637
Government Treasury	21,546		—		—		21,546
Common Equity Securities	32,400		—		—		32,400
Corporate Bonds	—		44,878		—		44,878
Sovereign/Non-US Debt	—		4,560		—		4,560
Total Investments	$	54,583	$	49,438	$	—	$	104,021


	(In Thousands)
	As of December 31, 2024
	Level 1		Level 2		Level 3		Total
Mutual Funds	$	31,187	$	—	$	—	$	31,187
Money Market Funds	293		—		—		293
Common Equity Securities	195		—		—		195
Corporate Bonds	42,974		—		—		42,974
Agency/US Debt	19,041		—		—		19,041
Sovereign/Non-US Debt	4,958		—		—		4,958
Total Investments	$	98,648	$	—	$	—	$	98,648

The following tables present Middlesex’s Other Benefits Plan assets measured and recorded at fair value within the fair value hierarchy:


	(In Thousands)
	As of December 31, 2025
	Level 1		Level 2		Level 3		Total
Money Market Funds	885		—		—		885
Cash	317		—		—		317
Equity Securities	41,150		—		—		41,150
Agency/US/State/Municipal Debt	—		18,148		—		18,148
Total Investments	$	42,352	$	18,148	$	—	$	60,500


	(In Thousands)
	As of December 31, 2024
	Level 1		Level 2		Level 3		Total
Mutual Funds	$	34,545	$	—	$	—	$	34,545
Money Market Funds	977		—		—		977
Agency/US/State/Municipal Debt	—		17,505		—		17,505
Total Investments	$	35,522	$	17,505	$	—	$	53,027

Schedule of Table Presents Awarded but not Yet Vested Share

The following table presents awarded but not yet vested share information for the plan:


	Shares(thousands)	Unearned Compensation (thousands)		Weighted Average Granted Price
Balance, January 1, 2021	83	$	1,931
Granted	11	1,151		$	105.17
Vested	(17)
Amortization of Compensation expense	—	(1,350)
Balance, December 31, 2022	77	1,732
Granted	15	1,165		$	77.63
Vested	(18)	—
Amortization of Compensation expense	—	(1,854)
Balance, December 31, 2023	74	1,043
Granted	19	1,003		$	52.50
Vested	(58)	—
Amortization of Compensation expense	—	(1,140)
Balance, December 31, 2024	35	906
Granted	24	1,540		$	64.10
Vested	(17)
Amortization of Compensation expense	—	(905)
Balance, December 31, 2025	42	1,541

Capitalization - Narrative (Details) $ / shares in Units, gal in Millions		1 Months Ended			12 Months Ended
	May 12, 2025 USD ($)	Feb. 19, 2026 USD ($)	Sep. 30, 2025 USD ($) shares	May 31, 2024 USD ($) loan	Dec. 31, 2025 USD ($) quarterlyDividend boardMember project $ / shares shares gal	Dec. 31, 2024 USD ($) shares	Dec. 31, 2023 USD ($) shares	Oct. 31, 2025 USD ($)	Sep. 30, 2024 USD ($)	Apr. 30, 2023 shares
Class of Stock [Line Items]
At-The-Market Program Common Stock Issuance					$ 29,547,000
Number of shares approved to issue and sell (in shares) \| shares										1,000,000.0
Proceeds from Issuance of Common Stock					$ 30,454,000	$ 974,000	$ 12,115,000
Preferred stock authorized (in shares) \| shares					120,000	120,000
Cumulative preferred stock, Nonredeemable shares outstanding (in shares) \| shares					13,000	16,000
Number of quarterly dividends in arrears triggering election of members to Board of Directors \| quarterlyDividend					4
Number of Board of Directors members entitled to elect upon quarterly dividends in arrears trigger \| boardMember					2
Convertible preferred shares available to convert (in shares)					1
Convertible preferred stock no par value (in dollars per share) \| $ / shares					$ 7.00
Preferred stock converted into common shares (in shares) \| shares					33,384
Proceeds from Issuance of Long-term Debt					$ 33,615,000	$ 2,296,000	$ 75,812,000
Weighted average interest rate					3.49%	3.64%
Loans Payable \| Tidewater
Class of Stock [Line Items]
Proceeds from Issuance of Long-term Debt					$ 900,000
Secured Debt \| Pinelands Water \| Subsequent Event
Class of Stock [Line Items]
Interest rate		6.17%
Debt repaid		$ 3,700,000
Secured Debt \| Pinelands Wastewater \| Subsequent Event
Class of Stock [Line Items]
Interest rate		6.17%
Debt repaid		$ 3,400,000
New Jersey SRF \| Loans Payable
Class of Stock [Line Items]
Maximum petitioned borrowing amount approved			$ 260,000,000.0
Borrowing amount			$ 300,000,000.0
5.99% FMBs due 2055 \| Secured Debt
Class of Stock [Line Items]
Borrowing amount								$ 30,000,000.0
Interest rate								5.99%
September 2024 Delaware SRF \| Loans Payable \| Tidewater
Class of Stock [Line Items]
Borrowing amount									$ 2,200,000
Interest rate									0.00%
Proceeds from Issuance of Long-term Debt					1,800,000
May 2024 Delaware SRF \| Loans Payable \| Tidewater
Class of Stock [Line Items]
Borrowing amount				$ 5,600,000
Interest rate				2.00%
Number of debt instruments \| loan				4
December 2025 Delaware SRF \| Loans Payable \| Tidewater
Class of Stock [Line Items]
Borrowing amount					$ 1,000,000.0
Interest rate					2.00%
December 2025 Delaware SRF \| Loans Payable \| Southern Shores
Class of Stock [Line Items]
Borrowing amount					$ 400,000
Interest rate					0.00%
2023 Delaware SRF \| Loans Payable \| Tidewater
Class of Stock [Line Items]
Proceeds from Issuance of Long-term Debt					$ 7,100,000
Number of active construction projects funded by debt instruments \| project					2
Carrying amount of debt					$ 8,300,000
Size of elevated storage tank (in gallons) \| gal					1
Amortizing Secured Notes And State Revolving Trust Notes \| Loans Payable
Class of Stock [Line Items]
Carrying amount of debt					$ 259,500,000	$ 229,800,000
Construction Advances \| Loans Payable
Class of Stock [Line Items]
Carrying amount of debt					$ 25,500,000	$ 22,600,000
Convertible Preferred Stock $7.00 Series
Class of Stock [Line Items]
At-The-Market Program Common Stock Issuance (in shares) \| shares					2,782
Cumulative preferred stock, Nonredeemable shares outstanding (in shares) \| shares					2,000	5,000
Convertible preferred stock per shares (in dollars per share) \| $ / shares					$ 7.00
Outstanding convertible stock, percentage					10.00%
Common Stock
Class of Stock [Line Items]
Shares converted (in shares) \| shares					12
Underwritten Public Offering and/or ATM Offering
Class of Stock [Line Items]
Maximum number of shares petitioned to issue and sell during offering (in shares) \| shares			2,500,000
ATM Equity Sales Agreement
Class of Stock [Line Items]
Aggregate gross sales price	$ 110,000,000.0
Number of shares issued and sold under agreement (in shares) \| shares					560,000
Weighted average price per share of shares issued and sold under agreement (in dollars per share) \| $ / shares					$ 53.54
Proceeds from Issuance of Common Stock					$ 29,500,000
Aggregate gross sales price of shares remaining to be issued under agreement					80,000,000.0
Common Stock
Class of Stock [Line Items]
At-The-Market Program Common Stock Issuance					$ 29,547,000
At-The-Market Program Common Stock Issuance (in shares) \| shares					560,000
Preferred Stock
Class of Stock [Line Items]
At-The-Market Program Common Stock Issuance					$ 300,000
Preferred stock authorized (in shares) \| shares					120,000
Cumulative preferred stock, Nonredeemable shares outstanding (in shares) \| shares					13,000
Preferred stock dividends					$ 0
Investment Plan \| Common Stock
Class of Stock [Line Items]
At-The-Market Program Common Stock Issuance					$ 900,000
At-The-Market Program Common Stock Issuance (in shares) \| shares					700,000
Outside Director Stock Compensation Plan
Class of Stock [Line Items]
Number of shares approved to issue and sell (in shares) \| shares					27,965
Maximum number of shares authorized for grant (in shares) \| shares					100,000
Outside Director Stock Compensation Plan \| Common Stock
Class of Stock [Line Items]
Granted shares (in shares) \| shares					6,318	7,570	4,608

Income Taxes - Schedule of Deferred Income Taxes (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Income Tax Disclosure [Abstract]
Utility Plant Related	$ 100,934	$ 95,877
Customer Advances	850
Customer Advances		(3,525)
Employee Benefits	8,778	7,888
Investment Tax Credits	128	181
Other	(215)
Other		814
Total Accumulated Deferred Income Taxes	$ 110,475	$ 101,235

CONSOLIDATED BALANCE SHEETS (Parentheticals) - USD ($) shares in Thousands, $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Statement of Financial Position [Abstract]
Allowance for credit losses	$ 1,625	$ 2,695
Common stock authorized (in shares)	40,000	40,000
Common stock outstanding (in shares)	18,521	17,887
Common stock issued (in shares)	18,521	17,887
Preferred stock authorized (in shares)	120	120
Preferred stock outstanding (in shares)	13	16
Preferred stock issued (in shares)	13	16

Organization, Summary of Significant Accounting Policies and Recent Developments

12 Months Ended

Dec. 31, 2025

Accounting Policies [Abstract]

Organization, Summary of Significant Accounting Policies and Recent Developments

(a) Organization - Middlesex Water Company (Middlesex or the Company) is the parent company and sole shareholder of Tidewater Utilities, Inc. (Tidewater), Pinelands Water Company (Pinelands Water) and Pinelands Wastewater Company (Pinelands Wastewater) (collectively, Pinelands), Utility Service Affiliates, Inc. (USA), Utility Service Affiliates (Perth Amboy) Inc. (USA-PA) and Twin Lakes Utilities, Inc. (Twin Lakes). Southern Shores Water Company, LLC (Southern Shores) and White Marsh Environmental Systems, Inc. (White Marsh) are wholly-owned subsidiaries of Tidewater. The terms “we,” “our,” and “us” collectively refer to Middlesex and its subsidiaries,

Middlesex has operated as a water utility in New Jersey since 1897 and in Delaware, through our wholly-owned subsidiary, Tidewater, since 1992. We are in the business of providing an essential water utility service for domestic, commercial, municipal, industrial and fire protection purposes. We also operate New Jersey municipal water, wastewater and storm water systems under contract and provide unregulated water and wastewater services in New Jersey and Delaware through our subsidiaries. Our rates charged to customers for water and wastewater services, the quality of services we provide and certain other matters are regulated in New Jersey and Delaware by the New Jersey Board of Public Utilities (NJBPU) and the Delaware Public Service Commission (DEPSC), respectively. Our USA, USA-PA and White Marsh subsidiaries are not regulated utilities.

(b) Principles of Consolidation – The financial statements for Middlesex are reported on a consolidated basis. All significant intercompany accounts and transactions have been eliminated. Other financial investments in which the Company holds a 50% or less voting interest, has significant influence and cannot exercise control over the operation and policies of the investments are accounted for under the equity method of accounting. Under the equity method of accounting, the Company records its investment interests in Non-Utility Assets and its percentage share of the earnings or losses of the investees in Other Income.

(c) System of Accounts – The Company’s regulated utilities maintain their accounts in accordance with the Uniform System of Accounts prescribed by the NJBPU and DEPSC.

(d) Regulatory Accounting - We maintain our books and records in accordance with accounting principles generally accepted in the United States of America (GAAP). Middlesex and certain of its subsidiaries, which account for 94% of Operating Revenues and 99% of Total Assets, are subject to regulation in the state in which they operate. Those companies are required to maintain their accounts in accordance with regulatory authorities’ rules and guidelines, which may differ from other authoritative accounting pronouncements. In those instances, the Company follows the guidance provided in Accounting Standards Codification (ASC) 980, Regulated Operations.

In accordance with ASC 980, Regulated Operations, costs and obligations are deferred if it is probable that these items will be recognized for rate-making purposes in future rates. Accordingly, we have recorded costs and obligations, which will be amortized over various future periods. Any change in the assessment of the probability of rate-making treatment will require us to change the accounting treatment of the deferred item. We have no reason to believe any of the deferred items that are recorded will be treated differently by the regulators in the future. For additional information, see Note 2 – Rate and Regulatory Matters.

(e) Retirement Benefit Plans - We maintain a noncontributory defined benefit pension plan (Pension Plan), which covers all active employees who were hired prior to April 1, 2007, as well as a defined contribution plan in which all employees are eligible to participate. In addition, the Company maintains an unfunded supplemental plan for certain of its executive officers. The Company has a retirement benefit plan other than pensions (Other Benefits Plan) for substantially all of its retired employees. Employees hired after March 31, 2007 are not eligible to participate in this plan. Coverage includes healthcare and life insurance.

The Company’s costs for providing retirement benefits are dependent upon numerous factors, including actual plan experience and assumptions of future experience. Retirement benefit plan obligations and expense are determined based on investment performance, discount rates and various other demographic factors related to the population participating in the Company’s retirement benefit plans, all of which can change significantly in future years. For more information on the Company’s Retirement Benefit Plans, see Note 7 – Employee Benefit Plans.

(f) Utility Plant – Utility Plant is stated at original cost as defined for regulatory purposes. Property accounts are charged with the cost of betterments and major replacements of property. Cost includes direct material, labor and indirect charges for pension benefits and payroll taxes. The cost of labor, materials, supervision and other expenses incurred in making repairs and maintenance of the properties is charged to the appropriate expense accounts. At December 31, 2025, there was

no event or change in circumstance that would indicate that the carrying amount of any long-lived asset was not recoverable.

(g) Depreciation – Depreciation is computed by each regulated subsidiary of the Company utilizing a rate approved by the applicable regulatory authority. The accumulated provision for depreciation is charged with the cost of property retired, less salvage. The following table sets forth the range of depreciation rates for the major utility plant categories used to calculate depreciation for the years ended December 31, 2025, 2024, and 2023. These rates have been approved by the NJBPU or DEPSC:


Source of Supply	1.15% - 3.44%	Transmission and Distribution (T&D):
Pumping	2.00% - 5.39%	T&D – Mains	1.10% - 3.13%
Water Treatment	1.65% - 7.09%	T&D – Services	2.12% - 3.16%
General Plant	2.08% - 17.84%	T&D – Other	1.61% - 4.63%
Wastewater Collection	1.42% - 1.81%

Non-regulated fixed assets consist primarily of office buildings, furniture and fixtures, and transportation equipment. These assets are recorded at original cost and depreciation is calculated based on the estimated useful lives, ranging from 3 to 42 years.

(h) Advances for Construction– Cash advances are provided to the Company by customers, real estate developers and builders in order to extend utility service to their properties. These transactions are recorded as Advances for Construction (CAC). Contractual refunds of CAC in the form of cash are made by the Company and are based on either additional operating revenues generated from new customers or as new customers are connected to the respective system. After all refunds are made and/or contract terms have expired, any remaining balance is transferred to Contributions in Aid of Construction (CIAC). For the twelve months ended December 31, 2025, the Company refunded $0.5 million of CAC.

CIAC – CIAC include direct non-refundable contributions of utility plant and/or cash and the portion of Advances for Construction that becomes non-refundable.

In accordance with regulatory requirements, Advances for Construction and CIAC are not depreciated. In addition, these amounts reduce the investment base for purposes of setting rates.

(i) Allowance for Funds Used During Construction (AFUDC) - Middlesex and its regulated subsidiaries capitalize AFUDC, which represents the cost of financing projects during construction. AFUDC is added to the construction costs of individual projects exceeding specific cost and construction period thresholds established for each company and then depreciated with the utility plant direct costs over the underlying assets’ estimated useful life. AFUDC is calculated using each company’s weighted cost of debt and equity as approved in their most recent respective regulatory rate order. The AFUDC rates for the years ended December 31, 2025, 2024 and 2023 for Middlesex and Tidewater are as follows:


	2025		2024		2023
Middlesex	6.64	%	6.64	%	6.35	%
Tidewater	7.04	%	7.92	%	7.92	%

(j) Accounts Receivable – We record bad debt expense based on a variety of factors such as our customers’ payment history, current economic conditions and trending reasonable and supportable forecasts on expected collectability of accounts receivable. The allowance for credit losses was $1.6 million and $2.7 million as of December 31, 2025 and 2024, respectively. For the years ended December 31, 2025, 2024 and 2023, bad debt expense was $0.3 million, $1.6 million and $1.0 million, respectively. For the years ended December 31, 2025, 2024 and 2023, write-offs were $1.4 million, $1.0 million and $1.2 million, respectively.

(k) Revenues - The Company’s revenues are primarily generated from regulated tariff-based water and wastewater utility services and non-regulated operation and maintenance contracts for services on water and wastewater systems owned by others. Revenue from contracts with customers is recognized when control of a promised good or service is transferred to customers at an amount that reflects the consideration to which the Company expects to be entitled in exchange for those goods and services.

The Company’s regulated revenue results from tariff-based water and wastewater utility services to residential, industrial, commercial, fire-protection and wholesale customers. Residential customers are billed quarterly or monthly while most industrial, commercial, fire-protection and wholesale customers are billed monthly. Payments by customers are due between 15 to 30 days after the invoice date. Revenue is recognized as the water and wastewater services are delivered to customers which includes an accrual of unbilled revenues estimated from the last meter reading date to the end of the

accounting period utilizing factors such as historical customer data and regional weather indicators. Unearned Revenues and Advance Service Fees include fixed service charge billings in advance to Tidewater customers recognized as service is provided to the customer.

Non-regulated service contract revenues consist of base service fees as well as fees for additional billable services provided to customers. Fees are billed monthly and are due within 30 days after the invoice date. The Company considers the amounts billed to represent the value of these services provided to customers. These contracts expire at various times through 2032 and contain remaining performance obligations for which the Company expects to recognize revenue in the future. These contracts also contain customary termination provisions.

Substantially all of the amounts included in operating revenues and accounts receivable are from contracts with customers.

The Company’s contracts do not contain any significant financing components.

The Company’s operating revenues are comprised of the following:


	(In Thousands)
	Years Ended December 31,
	2025		2024		2023
Regulated Tariff Sales
Residential	$	102,437	$	97,802	$	86,581
Commercial	30,436		31,833		23,945
Industrial	13,367		13,842		11,586
Fire Protection	15,116		14,188		12,582
Wholesale	20,702		21,003		19,117
Non-Regulated Contract Operations	12,504		13,085		12,320
Total Revenue from Contracts with Customers	$	194,562	$	191,753	$	166,131
Other Regulated Revenues	596		691		806
Other Non-Regulated Revenues	481		467		453
Inter-segment Elimination	(945)		(1,034)		(1,116)
Total Revenue	$	194,694	$	191,877	$	166,274

(l) Unamortized Debt Expense and Premiums on Long-Term Debt - Unamortized Debt Expense and Premiums on Long-Term Debt, included on the consolidated balance sheet in long-term debt, are amortized over the lives of the related debt.

(m) Income Taxes - Middlesex files a consolidated federal income tax return for the Company. Certain income and expense items are accounted for in different time periods for financial reporting than for income tax reporting purposes. The determination of our provision for income taxes requires the use of estimates and the interpretation and application of tax laws. Judgment is required in assessing the deductibility and recoverability of certain tax benefits. We use the asset and liability method to determine and record deferred tax assets and liabilities, representing future tax benefits and taxes payable, which result from the differences in basis recorded in GAAP financial statements and amounts recorded in the income tax returns. The deferred tax assets and liabilities are recorded utilizing the statutorily enacted tax rates expected to be in effect at the time the assets are realized and/or the liabilities settled. An offsetting valuation allowance is recorded when it is more likely than not that some or all of the deferred income tax assets won’t be realized. Any significant changes to the estimates and judgments with respect to the interpretations, timing or deductibility could result in a material change to earnings and cash flows. Investment tax credits have been deferred and are amortized over the estimated useful life of the related property. In the event there are interest and penalties associated with income tax adjustments from income tax authority examinations, these amounts will be reported under interest charges and other expense, respectively. For more information on income taxes, see Note 3 – Income Taxes.

Accounting guidance requires that we establish reserves for uncertain tax positions, if any, when it is more likely than not that the positions will not be sustained when challenged by taxing authorities. Any changes to the estimates and judgments with respect to the interpretations, timing or deductibility could result in a change to earnings and cash flows.

(n) Cash and Cash Equivalents - For purposes of reporting cash flows, the Company considers all highly liquid investments with original maturity dates of three months or less to be cash equivalents. Cash and cash equivalents represent bank balances and money market funds with investments maturing in less than 90 days. Restricted cash includes amounts held in escrow related to the acquisition of a subsidiary currently in receivership by another utility.

(o) Use of Estimates - Conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts in the financial statements. Actual results could differ from those estimates.

(p) Recent Accounting Pronouncements - The recently issued accounting standards and their impact on the Company as of December 31, 2025 are as follows:

Standard

Description

Date of Adoption

Application

Effect on the
Condensed
Consolidated
Financial Statements

Accounting Standards Update (ASU) 2023-09 “Improvements to Income Tax Disclosures”

The ASU amends certain income tax disclosure requirements, including adding requirements to present the reconciliation of income tax expense computed at the statutory rate to actual income tax expense using both percentages and amounts and providing a disaggregation of income taxes paid. Further, certain disclosures are eliminated, including the current requirement to disclose information on changes in unrecognized tax benefits in the next 12 months.

The ASU is effective for the Company beginning with its annual financial statements for the year ending December 31, 2025.

Prospective, with retrospective application also permitted.

The Company adopted ASU 2023-09 prospectively and has enhanced its income tax disclosures included in Note 3, Income Taxes, to comply with the requirements. The adoption of ASU 2023-09 did not have a material impact on the Company’s consolidated financial statements.

ASU 2024-03 “Disaggregation of Income Statement Expenses”

The ASU enhances disclosures related to income statement expenses to further disaggregate expenses in the footnotes to the financial statements. The standard requires disaggregation of any relevant expense caption presented on the face of the income statement that contains the following expense categories: purchases of inventory, employee compensation, depreciation, intangible asset amortization, and depletion. Further, the standard requires disclosure of the total amount and the entity’s definition of selling expenses.

The ASU is effective for the Company beginning with its annual financial statements for the year ending December 31, 2027.

Prospective, with retrospective application also permitted.

The Company is currently evaluating the requirements of ASU 2024-03.

ASU 2025-06 "Internal-Use Software"

This ASU removes all reference to prescriptive and sequential software development stages, requiring an entity to start capitalizing software costs when the following criteria are both met: (i) management has authorized and committed to funding the software project and (ii) it is probable that the project will be completed and the software will be used to perform the function intended. Further, the standard requires disclosure for all capitalized internal-use software costs and removes the requirement for intangibles disclosures for capitalized internal-use software.

The ASU is effective for the Company beginning with its annual financial statements for the year ending December 31, 2028.

Prospective, with a modified transition or retrospective application also permitted.

The Company is evaluating the impact of ASU 2025-06 on its Consolidated Financial Statements and the timing of adoption.

Short-term Borrowings - Narrative (Details) - Line of Credit - USD ($)	Feb. 19, 2026	Dec. 31, 2025	Jul. 31, 2025
Line of Credit Facility [Line Items]
Aggregate lines of credit		$ 148,000,000.0
CoBank, ACB (CoBank)
Line of Credit Facility [Line Items]
Aggregate lines of credit		20,000,000.0
CoBank, ACB (CoBank) \| Tidewater
Line of Credit Facility [Line Items]
Aggregate lines of credit			$ 20,000,000.0
PNC Bank
Line of Credit Facility [Line Items]
Aggregate lines of credit		$ 68,000,000.0
PNC Bank \| Subsequent Event
Line of Credit Facility [Line Items]
Aggregate lines of credit	$ 100,000,000

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
UTILITY PLANT:
Water Production	$ 328,496	$ 314,924
Transmission and Distribution	938,118	855,497
General	111,325	105,167
Construction Work in Progress	44,400	34,209
TOTAL	1,422,339	1,309,797
Less Accumulated Depreciation	275,132	254,425
UTILITY PLANT - NET	1,147,207	1,055,372
CURRENT ASSETS:
Cash and Cash Equivalents	2,800	4,226
Accounts Receivable, net of allowance for credit losses of $1,625 and $2,695, respectively in 2025 and 2024	19,213	18,842
Unbilled Revenues	9,361	10,764
Materials and Supplies (at average cost)	7,549	6,719
Prepayments	2,843	2,422
TOTAL CURRENT ASSETS	41,766	42,973
OTHER ASSETS:
Operating Lease Right of Use Asset	1,972	2,567
Regulatory Assets	110,284	101,783
Restricted Cash	1,675	0
Non-utility Assets - Net	12,354	11,760
Employee Benefit Plans	44,328	36,856
Other	6,151	3,863
TOTAL OTHER ASSETS	176,764	156,829
TOTAL ASSETS	1,365,737	1,255,174
CAPITALIZATION:
Common Stock, No Par Value, authorized 40,000, 18,521 and 17,887 outstanding in 2025 and 2024, respectively	279,148	248,202
Retained Earnings	214,883	197,061
TOTAL COMMON STOCKHOLDERS’ EQUITY	494,031	445,263
Preferred Stock, No Par Value, authorized 120, 13 and 16 outstanding in 2025 and 2024, respectively	1,343	1,635
Long-term Debt	378,874	352,822
TOTAL CAPITALIZATION	874,248	799,720
CURRENT LIABILITIES:
Current Portion of Long-term Debt	7,850	7,711
Notes Payable	28,250	23,000
Accounts Payable	31,326	28,050
Accrued Taxes	15,992	11,976
Accrued Interest	3,311	2,916
Unearned Revenues and Advanced Service Fees	497	1,476
Other	6,569	7,759
TOTAL CURRENT LIABILITIES	93,795	82,888
COMMITMENTS AND CONTINGENT LIABILITIES (Note 4)
OTHER LIABILITIES:
Advances for Construction	25,519	22,629
Lease Obligations	1,838	2,432
Accumulated Deferred Income Taxes	110,475	101,235
Regulatory Liabilities	68,437	64,557
Other	229	344
TOTAL OTHER LIABILITIES	206,498	191,197
CONTRIBUTIONS IN AID OF CONSTRUCTION	191,196	181,369
TOTAL CAPITALIZATION AND LIABILITIES	$ 1,365,737	$ 1,255,174

Cybersecurity Risk Management and Strategy Disclosure	12 Months Ended
Cybersecurity Risk Management and Strategy Disclosure	Dec. 31, 2025
Cybersecurity Risk Management, Strategy, and Governance [Line Items]
Cybersecurity Risk Management Processes for Assessing, Identifying, and Managing Threats [Text Block]	Cybersecurity Program The Company’s cybersecurity program is an integral element of the Company's overarching strategic plan and risk management system. The robustness of the cybersecurity initiatives directly impact the realization of the Company's mission, vision, and goals. Aligned with the National Institute of Standards and Technology Cyber Security Framework, the Company employs a comprehensive "defense-in-depth" strategy, deploying multiple security measures to safeguard its operational environment and data integrity systems. The Company continually evaluates and refines its cybersecurity program in response to key factors such as evolving threat landscapes, program maturation, gap analysis, and guidance from external security consultants. The Company’s cybersecurity program relies on three key pillars: People, Process and Technology (PPT) to deliver a robust cybersecurity program. The cybersecurity program includes various aspects of PPT, including, but not limited to: •Technology: Encryption, threat management, backups, monitoring, investigative support utilizing artificial intelligence embedded tools; •Identity and Access Control Management Tools: Multi-factor authentication, monitoring and alerting of privilege account access; •Cybersecurity Processes: Vulnerability scanning, penetration testing, and periodic assessments conducted by external security consultants; •Incident Response Training: Regularly assessed incident response preparedness through various incident response and disaster recovery exercises; and •Cyber Risk Awareness and Training: Frequent simulation exercises to heighten awareness of cybersecurity threats and educate our user community on preventative measures and reporting protocols. All employees participate in required periodic training with respect to cybersecurity risk and risk mitigation. Our Chief Technology Officer (CTO), with over 25 years of experience in various disciplines of information technology, oversees the cybersecurity program. Reporting to the Chief Executive Officer, the CTO provides regular briefs to the Board of Directors (the Board) and executive management, informing them about prevention, detection, mitigation, and remediation of cybersecurity incidents, as well as ongoing risks and threats. In our industry, the continuous functioning of information systems is of the utmost importance. Leveraging information technology systems, we collect, process and safeguard sensitive data and utilize automated tools to operate our plants. Cybersecurity threats encompass potential hazards such as malicious code, employee misconduct, advanced persistent threats, fraud, and phishing attacks. These risks have the potential to lead to information technology system failures, threat to water supply, or compromise of sensitive information. Our cybersecurity program aims to protect the uninterrupted availability of critical information technology resources. Regular assessments, conducted both internally and by third parties, evaluate our program against industry standards, including the National Institute of Standards and Technology Cybersecurity Standard and the Risk Management Framework. Although we have not experienced cybersecurity breaches or incidents that have significantly impacted our financial condition, results of operations, or business strategy, the effectiveness of our measures to prevent, detect, mitigate, or recover is based on currently known threats and recovery methods. There is no guarantee that cybersecurity breaches or incidents will not impact our business operations, strategy, financial condition, or operations. The ever-evolving landscape of cybersecurity threats introduces ongoing challenges. The Company recognizes the increasing frequency and sophistication of these threats. Despite implementing measures to secure operational and technology systems and fostering a culture of continuous improvement, the dynamic nature of cyber-attacks and vulnerabilities implies that these defenses may not be foolproof. Cybersecurity Risk Management Program and Strategy Cybersecurity risk management strategy is an integral component of our operations and our overall risk management process. Recognizing the dynamic nature of cybersecurity threats, we have implemented a comprehensive risk management program that aims to identify, assess, and mitigate potential risks. Our strategy involves a proactive approach, incorporating preventative measures, continuous monitoring, and adaptive response mechanisms. We prioritize the safeguarding of our operational network environment, sensitive data, including confidential business information and personal details of our customers and employees. Regular assessments conducted both internally and by third parties ensure our cybersecurity program aligns with industry standards. In addition to a dedicated cybersecurity team, we employ a defense-in-depth strategy, utilizing multiple security measures to protect our information technology system. Collaboration with third-party experts, industry peers and ongoing training initiatives ensures our cybersecurity strategy remains robust and responsive to evolving threats. We understand the importance of maintaining a vigilant and adaptive stance in the ever-evolving landscape of cybersecurity to safeguard our business operations, financial stability, and as a direct result, our overall success. Key elements of our cybersecurity risk mitigation approach are comprised of: •A dedicated cybersecurity team; •Collaboration with third-party managed detection and response resources for 24/7 monitoring and response; •Cybersecurity insurance to cover a portion of losses and damages resulting from cyber-attacks or security breaches; •An incident response team that is comprised of various departments required for an effective response; •Conducting periodic drills and exercises, including industry collaborations and participation from the executive team; •Continuous information security awareness training and phishing simulation exercises; •Regular security assessments to address evolving risks and threats; •Deployment of automation solutions to strengthen detection and response capabilities; •Utilizing services offered by the United States Department of Homeland Security to assist with resiliency planning; and •Active participation and collaboration with organizations such as the Cybersecurity and Infrastructure Security Agency, Water Information Sharing & Analysis Center, New Jersey Cybersecurity and Communications Integration Cell, Delaware Cybersecurity Advisory Council, and the NJBPU. Third-Party Relationships The Company utilizes partners and third-party service providers to help deliver safe and reliable water and wastewater services across its regulated operations. In connection with these relationships, we perform due diligence, cyber risk scoring, cybersecurity related contractual obligations, and periodic reviews of third-party control environments to ensure alignment with the Company's risk exposure, business requirements, and risk tolerances. We extend our cybersecurity focus to third-party service providers by evaluating and monitoring their cybersecurity risks. High-risk vendors undergo continuous monitoring, and we maintain contractual agreements that mandate our third-party providers’ commitment to managing cybersecurity risks, providing incident notifications, and being subject to cybersecurity audits.
Cybersecurity Risk Management Processes Integrated [Flag]	true
Cybersecurity Risk Management Processes Integrated [Text Block]	Cybersecurity Program The Company’s cybersecurity program is an integral element of the Company's overarching strategic plan and risk management system. The robustness of the cybersecurity initiatives directly impact the realization of the Company's mission, vision, and goals. Aligned with the National Institute of Standards and Technology Cyber Security Framework, the Company employs a comprehensive "defense-in-depth" strategy, deploying multiple security measures to safeguard its operational environment and data integrity systems.
Cybersecurity Risk Management Third Party Engaged [Flag]	true
Cybersecurity Risk Third Party Oversight and Identification Processes [Flag]	true
Cybersecurity Risk Materially Affected or Reasonably Likely to Materially Affect Registrant [Flag]	false
Cybersecurity Risk Board of Directors Oversight [Text Block]	Governance Structure and Oversight The Company’s cybersecurity governance framework is designed to ensure robust oversight, accountability, and continuous improvement in managing information technology and cybersecurity risks. Governance responsibilities are distributed across several key bodies and roles: Board of Directors Oversight •The Enterprise Risk Committee (Committee) of the Board of Directors serves as the primary oversight body for management of risk identification, assessment, and mitigation strategies related to information technology, cybersecurity, and data security risks. •The Committee will regularly review and evaluate the effectiveness of the Company’s cybersecurity program, ensuring alignment with the organization’s risk appetite and strategic objectives. •The Board of Directors receives periodic briefings from executive management, including updates on the evolving threat landscape, significant incidents, program enhancements, and the preparedness of internal response capabilities. Continuous Improvement and Accountability •The governance structure supports a culture of continuous improvement, required to adapt to the rapidly changing cybersecurity landscape. •Accountability is reinforced through clearly defined roles, responsibilities, and performance metrics, ensuring that all stakeholders from the Board of Directors to operational teams are engaged in maintaining and enhancing the Company’s cybersecurity posture.
Cybersecurity Risk Board Committee or Subcommittee Responsible for Oversight [Text Block]	The Enterprise Risk Committee (Committee) of the Board of Directors serves as the primary oversight body for management of risk identification, assessment, and mitigation strategies related to information technology, cybersecurity, and data security risks.
Cybersecurity Risk Process for Informing Board Committee or Subcommittee Responsible for Oversight [Text Block]	The Committee will regularly review and evaluate the effectiveness of the Company’s cybersecurity program, ensuring alignment with the organization’s risk appetite and strategic objectives. •The Board of Directors receives periodic briefings from executive management, including updates on the evolving threat landscape, significant incidents, program enhancements, and the preparedness of internal response capabilities.
Cybersecurity Risk Role of Management [Text Block]	The Company’s cybersecurity program is an integral element of the Company's overarching strategic plan and risk management system. The robustness of the cybersecurity initiatives directly impact the realization of the Company's mission, vision, and goals. Aligned with the National Institute of Standards and Technology Cyber Security Framework, the Company employs a comprehensive "defense-in-depth" strategy, deploying multiple security measures to safeguard its operational environment and data integrity systems. The Company continually evaluates and refines its cybersecurity program in response to key factors such as evolving threat landscapes, program maturation, gap analysis, and guidance from external security consultants. The Company’s cybersecurity program relies on three key pillars: People, Process and Technology (PPT) to deliver a robust cybersecurity program. The cybersecurity program includes various aspects of PPT, including, but not limited to: •Technology: Encryption, threat management, backups, monitoring, investigative support utilizing artificial intelligence embedded tools; •Identity and Access Control Management Tools: Multi-factor authentication, monitoring and alerting of privilege account access; •Cybersecurity Processes: Vulnerability scanning, penetration testing, and periodic assessments conducted by external security consultants; •Incident Response Training: Regularly assessed incident response preparedness through various incident response and disaster recovery exercises; and •Cyber Risk Awareness and Training: Frequent simulation exercises to heighten awareness of cybersecurity threats and educate our user community on preventative measures and reporting protocols. All employees participate in required periodic training with respect to cybersecurity risk and risk mitigation.
Cybersecurity Risk Management Positions or Committees Responsible [Flag]	true
Cybersecurity Risk Management Positions or Committees Responsible [Text Block]	Reporting to the Chief Executive Officer, the CTO provides regular briefs to the Board of Directors (the Board) and executive management, informing them about prevention, detection, mitigation, and remediation of cybersecurity incidents, as well as ongoing risks and threats.
Cybersecurity Risk Management Expertise of Management Responsible [Text Block]	Our Chief Technology Officer (CTO), with over 25 years of experience in various disciplines of information technology, oversees the cybersecurity program.
Cybersecurity Risk Process for Informing Management or Committees Responsible [Text Block]	Cybersecurity Risk Management Program and Strategy Cybersecurity risk management strategy is an integral component of our operations and our overall risk management process. Recognizing the dynamic nature of cybersecurity threats, we have implemented a comprehensive risk management program that aims to identify, assess, and mitigate potential risks. Our strategy involves a proactive approach, incorporating preventative measures, continuous monitoring, and adaptive response mechanisms. We prioritize the safeguarding of our operational network environment, sensitive data, including confidential business information and personal details of our customers and employees. Regular assessments conducted both internally and by third parties ensure our cybersecurity program aligns with industry standards. In addition to a dedicated cybersecurity team, we employ a defense-in-depth strategy, utilizing multiple security measures to protect our information technology system. Collaboration with third-party experts, industry peers and ongoing training initiatives ensures our cybersecurity strategy remains robust and responsive to evolving threats. We understand the importance of maintaining a vigilant and adaptive stance in the ever-evolving landscape of cybersecurity to safeguard our business operations, financial stability, and as a direct result, our overall success. Key elements of our cybersecurity risk mitigation approach are comprised of: •A dedicated cybersecurity team; •Collaboration with third-party managed detection and response resources for 24/7 monitoring and response; •Cybersecurity insurance to cover a portion of losses and damages resulting from cyber-attacks or security breaches; •An incident response team that is comprised of various departments required for an effective response; •Conducting periodic drills and exercises, including industry collaborations and participation from the executive team; •Continuous information security awareness training and phishing simulation exercises; •Regular security assessments to address evolving risks and threats; •Deployment of automation solutions to strengthen detection and response capabilities; •Utilizing services offered by the United States Department of Homeland Security to assist with resiliency planning; and •Active participation and collaboration with organizations such as the Cybersecurity and Infrastructure Security Agency, Water Information Sharing & Analysis Center, New Jersey Cybersecurity and Communications Integration Cell, Delaware Cybersecurity Advisory Council, and the NJBPU.
Cybersecurity Risk Management Positions or Committees Responsible Report to Board [Flag]	true

CONSOLIDATED STATEMENTS OF CAPITAL STOCK AND LONG-TERM DEBT - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Common Stock, No Par Value
Shares Authorized
Shares Outstanding	279,148	248,202
Retained Earnings	214,883	197,061
TOTAL COMMON STOCKHOLDERS’ EQUITY	494,031	445,263
Cumulative Preferred Stock, No Par Value:
Shares Authorized
Shares Outstanding
TOTAL PREFERRED STOCK	1,343	1,635
Long-term Debt:
SUBTOTAL LONG-TERM DEBT	385,683	359,386
Add: Premium on Issuance of Long-term Debt	6,148	6,339
Less: Unamortized Debt Expense	(5,107)	(5,192)
Less: Current Portion of Long-term Debt	(7,850)	(7,711)
TOTAL LONG-TERM DEBT	378,874	352,822
FMBs
Long-term Debt:
SUBTOTAL LONG-TERM DEBT	301,172	274,602
Amortizing Secured Notes
Long-term Debt:
SUBTOTAL LONG-TERM DEBT	63,971	66,889
State Revolving Trust Notes
Long-term Debt:
SUBTOTAL LONG-TERM DEBT	20,540	17,895
Convertible Preferred Stock $7.00 Series
Cumulative Preferred Stock, No Par Value:
TOTAL PREFERRED STOCK	264	556
Nonredeemable Preferred Stock $7.00 Series
Cumulative Preferred Stock, No Par Value:
TOTAL PREFERRED STOCK	79	79
Nonredeemable Preferred Stock $4.75 Series
Cumulative Preferred Stock, No Par Value:
TOTAL PREFERRED STOCK	$ 1,000	$ 1,000

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
CASH FLOWS FROM OPERATING ACTIVITIES:
Net Income	$ 42,822	$ 44,351	$ 31,524
Adjustments to Reconcile Net Income to
Depreciation and Amortization	32,495	28,038	29,442
Provision for Deferred Income Taxes and Investment Tax Credits	(5,234)	(1,605)	(5,599)
Equity Portion of Allowance for Funds Used During Construction (AFUDC)	(977)	(743)	(1,458)
Cash Surrender Value of Life Insurance	(296)	(308)	(300)
Stock Compensation Expense	1,237	1,537	2,214
Changes in Assets and Liabilities:
Accounts Receivable	(371)	(670)	(2,154)
Unbilled Revenues	1,403	(1,467)	(638)
Materials and Supplies	(830)	253	(795)
Prepayments	(421)	(589)	791
Accounts Payable	1,296	2,574	2,771
Accrued Taxes	4,016	1,441	(1,627)
Accrued Interest	395	(222)	603
Employee Benefit Plans	(5,380)	(3,696)	(1,340)
Unearned Revenue and Advanced Service Fees	(979)	86	25
Recovered Costs Litigation Settlement	0	(9,031)	0
Other Assets and Liabilities	(6,580)	(1,219)	(677)
NET CASH PROVIDED BY OPERATING ACTIVITIES	62,596	58,730	52,782
CASH FLOWS FROM INVESTING ACTIVITIES:
Utility Plant Expenditures, Including AFUDC-Debt of $641 in 2025, $511 in 2024 and $975 in 2023	(96,354)	(74,622)	(90,179)
Acquisition of Water Systems	(4,607)	0	0
NET CASH USED IN INVESTING ACTIVITIES	(100,961)	(74,622)	(90,179)
CASH FLOWS FROM FINANCING ACTIVITIES:
Redemption of Long-term Debt	(7,317)	(7,646)	(17,463)
Proceeds from Issuance of Long-term Debt	33,615	2,296	75,812
Net Short-term Bank Borrowings	5,250	(19,750)	(12,750)
Proceeds from Litigation Settlement, net	0	63,635	0
Deferred Debt Issuance Expense	(142)	(54)	(131)
Common Stock Issuance Expense	(667)	0	(10)
Payment of Grantee Withholding Taxes in Exchange for Restricted Stock	(371)	(1,468)	(619)
Proceeds from Issuance of Common Stock	30,454	974	12,115
Payment of Common Dividends	(24,924)	(23,408)	(22,441)
Payment of Preferred Dividends	(76)	(109)	(120)
Construction Advances and Contributions-Net	2,792	3,258	1,566
NET CASH PROVIDED BY FINANCING ACTIVITIES	38,614	17,728	35,959
NET CHANGES IN CASH, CASH EQUIVALENTS AND RESTRICTED CASH	249	1,836	(1,438)
CASH, CASH EQUIVALENTS AND RESTRICTED CASH AT BEGINNING OF PERIOD	4,226	2,390	3,828
CASH, CASH EQUIVALENTS AND RESTRICTED CASH AT END OF PERIOD	$ 4,475	$ 4,226	$ 2,390

Income Taxes - Schedule of Paid Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Income Tax Paid, by Individual Jurisdiction [Line Items]
Federal taxes Paid	$ 236
Total State Taxes Paid	1,403
Total Income Taxes Paid	1,639	$ 3,169	$ 2,962
State Taxes Paid-New Jersey
Income Tax Paid, by Individual Jurisdiction [Line Items]
Total State Taxes Paid	307
State Taxes Paid-Delaware
Income Tax Paid, by Individual Jurisdiction [Line Items]
Total State Taxes Paid	1,092
State Taxes Paid-Other
Income Tax Paid, by Individual Jurisdiction [Line Items]
Total State Taxes Paid	$ 4

Employee Benefit Plans - Schedule of Allocation of Plan Assets (Details)	Dec. 31, 2025	Dec. 31, 2024
Pension Plan
Schedule of Allocation of Plan Assets [Line Items]
Actual Allocation, Percentage	100.00%	100.00%
Other Benefits Plan
Schedule of Allocation of Plan Assets [Line Items]
Actual Allocation, Percentage	100.00%	100.00%
Equity Securities \| Pension Plan
Schedule of Allocation of Plan Assets [Line Items]
Actual Allocation, Percentage	51.90%	31.80%
Target Allocation, Percentage	30.00%
Equity Securities \| Other Benefits Plan
Schedule of Allocation of Plan Assets [Line Items]
Actual Allocation, Percentage	68.00%	65.20%
Target Allocation, Percentage	65.00%
Debt Securities \| Pension Plan
Schedule of Allocation of Plan Assets [Line Items]
Actual Allocation, Percentage	47.50%	67.90%
Target Allocation, Percentage	68.00%
Debt Securities \| Other Benefits Plan
Schedule of Allocation of Plan Assets [Line Items]
Actual Allocation, Percentage	30.00%	33.00%
Target Allocation, Percentage	33.00%
Cash \| Pension Plan
Schedule of Allocation of Plan Assets [Line Items]
Actual Allocation, Percentage	0.60%	0.30%
Target Allocation, Percentage	2.00%
Cash \| Other Benefits Plan
Schedule of Allocation of Plan Assets [Line Items]
Actual Allocation, Percentage	2.00%	1.80%
Target Allocation, Percentage	2.00%

Capitalization (Tables)

12 Months Ended

Dec. 31, 2025

Equity [Abstract]

Schedule of Long-Term Debt

The aggregate annual principal repayment obligations as of December 31, 2025 for all long-term debt over the next five years and thereafter are shown below:


Year	(In Millions) Annual Maturities

2026	$	7.9
2027	7.5
2028	7.2
2029	6.7
2030	5.8
Thereafter	350.8

Schedule of Basic and Diluted Earnings Per Share

The following table presents the calculation of basic and diluted earnings per share (EPS) of common stock for the years ended December 31, 2025, 2024 and 2023. Basic EPS is computed on the basis of the weighted average number of shares outstanding. Diluted EPS assumes the conversion of the Convertible Preferred Stock $7.00 Series.


	(In Thousands, Except Per Share Amounts)
	2025			2024			2023
Basic:	Income		Shares	Income		Shares	Income		Shares
Net Income	$	42,822	18,096	$	44,351	17,842	$	31,524	17,732
Preferred Dividend	(76)			(112)			(120)
Earnings Applicable to Common Stock	$	42,746	18,096	$	44,239	17,842	$	31,404	17,732
Basic EPS	$	2.36		$	2.48		$	1.77
Diluted:
Earnings Applicable to Common Stock	$	42,746	18,096	$	44,239	17,842	$	31,404	17,732
Convertible Preferred $7.00 Series Dividend	24		41	46		104	67		115
Adjusted Earnings Applicable to Common Stock	$	42,770	18,137	$	44,285	17,946	$	31,471	17,847
Diluted EPS	$	2.36		$	2.47		$	1.76

Schedule of Carrying Amount and Fair Value of the Bonds

The carrying amount and fair value of the Bonds were as follows:


	(In Thousands)
	At December 31,
	2025				2024
	Carrying Amount		Fair Value		Carrying Amount		Fair Value
FMBs	$	126,172	$	120,430	$	129,602	$	125,067

Organization, Summary of Significant Accounting Policies and Recent Developments - Schedule of Range of Depreciation Rates for the Major Utility Plant Categories (Details)	12 Months Ended
	Dec. 31, 2025
Minimum \| Source of Supply
Public Utilities, General Disclosures [Line Items]
Composite depreciation rate for plants in service	1.15%
Minimum \| Pumping
Public Utilities, General Disclosures [Line Items]
Composite depreciation rate for plants in service	2.00%
Transmission and distribution rate	1.10%
Minimum \| Water Treatment
Public Utilities, General Disclosures [Line Items]
Composite depreciation rate for plants in service	1.65%
Transmission and distribution rate	2.12%
Minimum \| General Plant
Public Utilities, General Disclosures [Line Items]
Composite depreciation rate for plants in service	2.08%
Transmission and distribution rate	1.61%
Minimum \| Wastewater Collection
Public Utilities, General Disclosures [Line Items]
Composite depreciation rate for plants in service	1.42%
Maximum \| Source of Supply
Public Utilities, General Disclosures [Line Items]
Composite depreciation rate for plants in service	3.44%
Maximum \| Pumping
Public Utilities, General Disclosures [Line Items]
Composite depreciation rate for plants in service	5.39%
Transmission and distribution rate	3.13%
Maximum \| Water Treatment
Public Utilities, General Disclosures [Line Items]
Composite depreciation rate for plants in service	7.09%
Transmission and distribution rate	3.16%
Maximum \| General Plant
Public Utilities, General Disclosures [Line Items]
Composite depreciation rate for plants in service	17.84%
Transmission and distribution rate	4.63%
Maximum \| Wastewater Collection
Public Utilities, General Disclosures [Line Items]
Composite depreciation rate for plants in service	1.81%

Cover - USD ($)	12 Months Ended
Cover - USD ($)	Dec. 31, 2025	Feb. 17, 2026	Jun. 30, 2025
Cover [Abstract]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2025
Current Fiscal Year End Date	--12-31
Document Transition Report	false
Entity File Number	0-422
Registrant Name	MIDDLESEX WATER COMPANY
Entity Incorporation, State or Country Code	NJ
Entity Tax Identification Number	22-1114430
Entity Address, Address Line One	485C Route 1 South
Entity Address, Address Line Two	Suite 400
Entity Address, City or Town	Iselin
Entity Address, State or Province	NJ
Entity Address, Postal Zip Code	08830
City Area Code	(732)
Local Phone Number	634-1500
Title of 12(b) Security	Common Stock, No Par Value
Trading Symbol	MSEX
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	true
Document Financial Statement Error Correction [Flag]	false
Entity Shell Company	false
Entity Public Float			$ 954,602,892
Entity Common Stock, Shares Outstanding		18,521,933
Documents Incorporated by Reference	Proxy Statement to be filed in connection with the Registrant’s Annual Meeting of Stockholders to be held on May 19, 2026, which will be filed with the Securities and Exchange Commission within 120 days of the end of our 2025 fiscal year, is incorporated by reference into Part III of this Annual Report on Form 10-K to the extent described herein.
Amendment Flag	false
Document Fiscal Year Focus	2025
Document Fiscal Period Focus	FY
Entity Central Index Key	0000066004

Supplemental Cash Flows Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
SUPPLEMENTAL DISCLOSURE OF NON-CASH ACTIVITY:
Utility Plant received as Construction Advances and Contributions	$ 9,924	$ 8,968	$ 7,259
Accrued Payables for Utility Plant	9,901	8,109	10,251
Litigation Settlement Receivable	0	(6,237)	69,872
Litigation Settlement Payable	0	(6,237)	6,237
Conversion of Preferred Stock Into Common Stock	292	449	0
Cash Paid During Period [Abstract]
Interest	13,459	14,485	12,762
Interest Capitalized	640	511	975
Income Taxes	$ 1,639	$ 3,169	$ 2,962

Capitalization - Schedule of Basic and Diluted Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Equity [Abstract]
Convertible preferred stock, conversion price (in dollars per share)	$ 7.00	$ 7.00	$ 7.00
Basic:
Net Income	$ 42,822	$ 44,351	$ 31,524
Net Income (in shares)	18,096	17,842	17,732
Preferred Dividend	$ (76)	$ (112)	$ (120)
Earnings Applicable to Common Stock	$ 42,746	$ 44,239	$ 31,404
Basic EPS (in dollars per share)	$ 2.36	$ 2.48	$ 1.77
Diluted:
Earnings Applicable to Common Stock	$ 42,746	$ 44,239	$ 31,404
Earnings Applicable to Common Stock (in Shares)	18,096	17,842	17,732
Convertible Preferred $7.00 Series Dividend	$ 24	$ 46	$ 67
Convertible Preferred $7.00 Series Dividend (in shares)	41	104	115
Adjusted Earnings Applicable to Common Stock	$ 42,770	$ 44,285	$ 31,471
Adjusted Earnings Applicable to Common Stock (in shares)	18,137	17,946	17,847
Diluted EPS (in dollars per share)	$ 2.36	$ 2.47	$ 1.76

Supplemental Cash Flows Information (Tables)

12 Months Ended

Dec. 31, 2025

Supplemental Cash Flow Elements [Abstract]

Schedule of Cash Flow, Supplemental Disclosures

The Company paid income taxes as follows:


	Year Ended
	December 31, 2025
Federal taxes Paid	$	236

State Taxes Paid-New Jersey	307
State Taxes Paid-Delaware	1,092
State Taxes Paid-Other	4
Total State Taxes Paid	$	1,403

Total Income Taxes Paid	$	1,639


(in thousands)	2025		2024		2023
SUPPLEMENTAL DISCLOSURE OF NON-CASH ACTIVITY:
Utility Plant received as Construction Advances and Contributions	$	9,924	$	8,968	$	7,259
Accrued Payables for Utility Plant	9,901		8,109		10,251
Litigation Settlement Receivable	—		(6,237)		69,872
Litigation Settlement Payable	—		(6,237)		6,237
Conversion of Preferred Stock Into Common Stock	292		449		—

SUPPLEMENTAL DISCLOSURE OF CASH FLOWS INFORMATION:
Cash Paid During the Year for:
Interest	13,459		14,485		12,762
Interest Capitalized	640		511		975
Income Taxes	1,639		3,169		2,962

Rates and Regulatory Matters

12 Months Ended

Dec. 31, 2025

Regulated Operations [Abstract]

Rates and Regulatory Matters

Middlesex Rate Matters

In February 2026, the NJBPU approved the settlement agreement in our general base rate application between Middlesex and Pinelands, NJBPU Staff and the New Jersey Rate Payer Advocate, with new rates effective February 23, 2026. The NJBPU order approved an increase in our annual operating revenues by $14.5 million based on an authorized return on common equity of 9.6% and a common equity ratio of 54.25%. Included in the settlement agreement, Middlesex and Pinelands customers will receive a one-time bill credit totaling $3.3 million for the refund by New Jersey and overcollection of New Jersey Gross Receipts Taxes. In addition, Middlesex customers will receive a $3.3 million credit over 12 months from the proceeds of a multi-distict litigation (MDL) settlement agreement between Middlesex and manufacturers of Perfluoroalkyl Substances (PFAS) (for further information on the MDL settlement, see MDL Settlement below).

In February 2026, the NJBPU approved the joint petition filed by Middlesex and Pinelands for a Resiliency and Environmental System Improvement Charge (RESIC) Foundational Filing, which allows for the recovery of certain costs of investments for the three-year period ending October 2028 related to compliance with requirements to address existing and emerging chemical elements or compound, installation of new plant or equipment or replacement of existing plant or equipment to further maintain, enhance, or improve resiliency, health, safety or environmental protection for Middlesex and Pinelands’ customers, employees or the public and addressing treatment media and related equipment for both existing and emerging chemical elements and compounds. Under the RESIC program, Middlesex and Pinelands submit semi-annual surcharge filings to the NJBPU for qualifying capital investments completed every six-months to be recovered up to $3.6 million or 2.5% of total annual revenues included in their February 2026 base rate increase.

In February 2026, the NJBPU approved the joint petition filed by Middlesex and Pinelands Water for a Distribution System Improvement Charge (DSIC) Foundational Filing, which allows for the recovery of investments in qualifying capital improvements to their water distribution system for the three-year period ending October 2028. Under the DSIC program, Middlesex and Pinelands Water submit semi-annual surcharge filings to the NJBPU for qualifying capital investments completed every six months to be recovered up to $7.1 million or 5% of total annual revenues included in their February 2026 base rate increase.

In January 2026, the NJBPU approved the joint petition filed by Middlesex, Pinelands Water and Pinelands Wastewater to consolidate the three entities into Middlesex through a corporate reorganization. The reorganization is expected to deliver operational efficiencies and enhanced benefits for customers across multiple areas. The merger is expected to be finalized in the first quarter of 2026.

In November 2025, the NJBPU approved the fourth Middlesex DSIC rate, effective December 1, 2025 that was expected to result in $0.9 million of annual revenues, which is in addition to the existing $2.3 million of annual revenues from previous DSIC filings. Middlesex's DSIC rate resets to zero in connection with Middlesex's February 2026 base rate increase.

In February 2025, the NJBPU approved Middlesex’s petition to reset its Purchased Water Adjustment Clause (PWAC) tariff rate to recover additional annual costs of $0.5 million, primarily for the purchase of treated water from a nonaffiliated water utility regulated by the NJBPU. The new PWAC rate became effective March 1, 2025. A PWAC is a rate mechanism that allows for the recovery of increased purchased water costs between base rate case filings. The PWAC is reset to zero in connection with Middlesex's February 2026 base rate increase.

The NJBPU-approved Middlesex Lead Service Line Replacement (LSLR) Plan continues and costs of $0.3 million for replacing customer-owned lead service line which were incurred between January 2025 through June 2025 are expected to be recovered between September 2025 and February 2026. Costs of $0.3 million incurred between July 2025 through December 2025 are expected to be recovered between March 2026 and August 2026. The LSLR surcharge is required to be reset every six months over the life of the LSLR Plan. Cost recovery for replacing Company-owned lead service lines are recoverable through traditional rate making in connection with general rate case filings.

Tidewater Rate Matters

In February 2026, the DEPSC approved the March 2026 refund of $1.1 million to Tidewater customers resulting from the proceeds of the MDL settlement agreement between Tidewater and manufacturers of PFAS. For further information, see discussion in MDL Settlement below.

In January 2026, Tidewater completed the acquisition of the water utility assets of the Pinewood Acres' water utility assets, as approved by the DEPSC, for $0.2 million. Pinewood Acres serves approximately 350 customers in Kent County, Delaware.

In December 2025, the DEPSC approved the Tidewater DSIC rate, effective January 1, 2026,. In Tidewater''s regulatory filing related to this matter, Tidewater indicated that the DSIC rate was expected to result in $0.3 million of semi-annual revenues from January 2026 to June 2026.

In July 2025, the DEPSC approved the settlement agreement in our general base rate application between Tidewater, DEPSC Staff and the Delaware Division of the Public Advocate, with new rates effective July 3, 2025. The DEPSC order approved an increase in our annual operating revenues by $5.5 million based on an authorized return on common equity of 9.5% and a common equity ratio of 53.5%. In addition, Tidewater refunded approximately $1.1 million of excess deferred income taxes associated with the Tax Cuts and Jobs Act of 2017 between July 2025 and December 2025, including $0.4 million of interest.

In April 2025, Tidewater completed the acquisition of the water utility assets of the Town of Ocean View, Delaware (Ocean View), as authorized by the DEPSC, for approximately $4.6 million. Ocean View serves approximately 900 customers in Sussex County, Delaware, who had been receiving water supply from Tidewater since the system was constructed in 2008.

In September 2024, the DEPSC approved Tidewater’s petition to recover up to $2.1 million of costs associated with Tidewater’s obligation to identify and inventory lead service lines throughout Tidewater’s service area, as required by federal law and Delaware regulations. Recovery of these costs began February 1, 2025 and is expected to continue through January 2028. Through December 31, 2025, Tidewater has spent $1.9 million to identify and inventory lead service lines.

MDL Settlement

Several of the Company’s utility subsidiaries are parties to the aforementioned MDL lawsuit against manufacturers of certain PFAS for damages, contribution and reimbursement of costs incurred and continuing to be incurred to address the presence of such PFAS in public water supply systems owned and operated by these utility subsidiaries and throughout their service areas. Settlements with several defendants in the MDL have received final approval by the MDL court. The Company timely submitted to the MDL court its Phase One claim forms under settlement agreements with defendants 3M Company, DuPont de Nemours, Inc., Tyco Fire Products LP and BASF Corporation and began receiving settlement payments in 2025.

Southern Shores Rate Matters

Southern Shores provides water service to a 2,200 unit condominium community in Sussex County, Delaware under a DEPSC-approved agreement expiring December 31, 2029. Under the agreement, rates are increased annually by the lesser of the regional Consumer Price Index or 3%. Additionally, when there are unanticipated capital expenditures or regulatory related changes in operating expenses exceed certain annual thresholds, rates are increased. In 2024 and 2025, capital expenditures did exceed the established threshold. Effective January 1, 2025 and January 1, 2026, Southern Shores rates were increased $0.1 million, or 6.51%,. and $0.1 million, or 4.89%, respectively.

Regulatory Matters

We have recorded certain costs as regulatory assets because we expect full recovery of, or are currently recovering, these costs in the rates we charge customers. These deferred costs have been excluded from rate base and, therefore, we are not earning a return on the unamortized balances. We record regulatory liabilities for amounts expected to be refunded to customers in the rate making process. These items are detailed as follows:


	(In Thousands)
	December 31,
Regulatory Assets	2025		2024
Income Taxes (a)	$	97,300	$	89,825
Other (b)	12,984		11,958
Total	$	110,284	$	101,783

Regulatory Liabilities
Income Taxes (c)	$	25,585	$	27,380
Cost of Removal (d)	22,037		20,595
Employee Benefit Plans (e)	11,526		9,435
Lawsuit Settlement (f)	1,598		5,334
New Jersey Revenue Taxes (g)	3,258		1,813
MDL Settlement (h)	$	4,433	$	—
Total	$	68,437	$	64,557

(a)The recovery period for income taxes is dependent upon when the temporary differences between the tax and book treatment of various items reverse.

(b)Other primarily includes deferred costs for rate cases and tank painting.

(c)The 2017 Tax Act reduced the statutory corporate federal income tax rate from 35% to 21%. The tariff rates charged to customers effective prior to 2018 in the Company’s regulated companies include recovery of income taxes at the statutory rate in effect at the time those rates were approved by the respective state public utility commissions. The Company has recorded regulatory liabilities for excess income taxes collected through rates due to the lower income tax rate under the 2017 Tax Act. These regulatory liabilities are largely related to utility plant depreciation deduction timing differences, which are subject to Internal Revenue Service (IRS) normalization rules. The IRS rules limit how quickly the excess taxes attributable to accelerated taxes can be returned to customers. The current base rates for Middlesex, Pinelands and Tidewater customers reflect the impact of the 2017 Tax Act.

(d)The Company uses composite depreciation rates for its regulated utility assets, which is currently an acceptable method under GAAP and is widely used in the utility industry. Historically, under the composite depreciation method, the anticipated costs of removing assets upon retirement are provided for over the life of those assets as a component of depreciation expense. The Company recovers certain asset retirement costs through rates charged to customers as an approved component of depreciation expense.

(e)Retirement benefits include pension and other retirement benefits that have been recorded on the Consolidated Balance Sheet in accordance with the guidance provided in ASC 715, Compensation – Retirement Benefits. These amounts represent obligations less than current funding.

(f)The net proceeds available to Middlesex from the 3M Settlement Agreement were recorded as a regulatory liability and are being used for future related operating and maintenance costs.

(g)Revenue-related taxes paid by the Company's New Jersey Regulated subsidiaries, and reflected in those subsidiaries current base rates, were above enacted rates and will be refunded back to customers in a future rate proceeding.

(h)Proceeds received by Middlesex and Tidewater from the settlement of the MDL lawsuit against manufacturers of PFAS that will be refunded to customers. For additional information, see Middlesex and Tidewater Rate Matters above.

Business Segment Data

12 Months Ended

Dec. 31, 2025

Segment Reporting [Abstract]

Business Segment Data

The Company’s Chief Operating Decision Maker (CODM) consists of the Company’s Chief Executive Officer, Chief Financial Officer, and Chief Operating Officer. The CODM evaluates segment performance and profitability using net

income. This metric provides a clear, consistent basis for analyzing the financial results of each segment and supports decision-making regarding the allocation of resources.

Resource allocation to the Company’s regulated and non-regulated segments begins with the annual budgeting process, which establishes initial funding and resource levels for each segment. The budget incorporates key financial and operational inputs, including anticipated revenues, expenses, capital and financing requirements, aligning with the Company’s strategic objectives and regulatory obligations. The CODM reviews budget-to-actual variances on a monthly, quarterly and year to-date basis and makes interim decisions to reallocate resources among segments as needed, ensuring a timely and effective response to changing conditions. For the regulated segment, the CODM uses this assessment to determine whether the segment is achieving its regulatory authorized rate of return.

The segments follow the same accounting policies as described in Note 1 – Organization, Summary of Significant Accounting Policies and Recent Developments. Segment profit or loss is based on Net Income. Expenses used to determine operating income before taxes are charged directly to each segment or are allocated based on the applicable cost allocation factors. Assets allocated to each segment are based upon specific identification of such assets provided by Company records. The effects of all intra-segment and/or intercompany transactions are eliminated in the consolidated financial statements.

The Company has identified two reportable segments. One is the regulated business of collecting, treating and distributing water on a retail and wholesale basis to residential, commercial, industrial and fire protection customers in parts of New Jersey and Delaware and includes Middlesex, Tidewater, Pinelands Water and Southern Shores. This segment also includes a regulated wastewater system in New Jersey, Pinelands Wastewater. The Company is subject to regulations as to its rates, services and other matters by the states of New Jersey and Delaware with respect to utility service within these states. The other segment is primarily comprised of non-regulated contract services for the operation and maintenance of municipal and private water and wastewater systems in New Jersey and Delaware and includes USA, USA-PA, and White Marsh.


	(In Thousands)
	Years Ended December 31,
Operation by Segments	2025		2024		2023
Revenues:
Regulated	$	182,654	$	179,359	$	154,617
Non – Regulated	12,985		13,552		12,773
Total Reportable Segments	195,639		192,911		167,390
Inter-segment Elimination	(945)		(1,034)		(1,116)
Consolidated Revenues	$	194,694	$	191,877	$	166,274

Operating Expenses
Purchased Water:
Regulated	$	8,458	$	8,064	$	9,144
Non – Regulated	—		—		—
Total Reportable Segments	8,458		8,064		9,144
Inter-segment Elimination	(464)		(567)		(663)
Consolidated Purchased Water	$	7,994	$	7,497	$	8,481

Other Operations and Maintenance Expenses:
Regulated	$	75,293	$	76,483	$	66,670
Non – Regulated	8,485		8,850		8,415
Total Reportable Segments	83,778		85,333		75,085
Inter-segment Elimination	(481)		(467)		(453)
Consolidated Other Operations and Maintenance Expenses	$	83,297	$	84,866	$	74,632

Other Taxes:
Regulated	$	21,675	$	21,644	$	18,504
Non – Regulated	239		230		240
Consolidated Other Taxes	$	21,914	$	21,874	$	18,744

Depreciation:
Regulated	$	26,844	$	24,173	$	24,931
Non – Regulated	269		257		263
Consolidated Depreciation	$	27,113	$	24,430	$	25,194

Operating Income:
Regulated	$	50,865	$	49,462	$	35,820
Non – Regulated	3,511		3,748		3,403
Consolidated Operating Income	$	54,376	$	53,210	$	39,223

Other Income (Expense), Net:
Regulated	$	8,001	$	12,195	$	6,637
Non – Regulated	236		281		214
Total Reportable Segments	8,237		12,476		6,851
Inter-segment Elimination	(675)		(407)		(366)
Consolidated Other Income, Net	$	7,562	$	12,069	$	6,485


	(In Thousands)
	Years Ended December 31,
Operation by Segments (continued)	2025		2024		2023
Interest Expense:
Regulated	$	14,970	$	14,430	$	13,508
Non – Regulated	—		—		—
Total Reportable Segments	14,970		14,430		13,508
Inter-segment Elimination	(675)		(407)		(365)
Consolidated Interest Expense	$	14,295	$	14,023	$	13,143

Income Taxes:
Regulated	$	3,637	5,653		(146)
Non – Regulated	1,184		1,252		1,187
Consolidated Income Taxes	$	4,821	$	6,905	$	1,041

Net Income:
Regulated	$	40,258	$	41,575	$	29,094
Non – Regulated	2,564		2,776		2,430
Consolidated Net Income	42,822		44,351		31,524

Capital Expenditures:
Regulated	$	96,015	$	74,584	$	90,047
Non – Regulated	339		38		132
Total Capital Expenditures	$	96,354	$	74,622	$	90,179


	(In Thousands)
	As of December 31, 2025		As of December 31, 2024
Assets:
Regulated	$	1,377,391	$	1,264,472
Non – Regulated	9,076		7,671
Total Reportable Segments	1,386,466		1,272,143
Inter-segment Elimination	(20,730)		(16,969)
Consolidated Assets	$	1,365,737	$	1,255,174

- Definition

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

+ References

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-URI https://asc.fasb.org/1943274/2147482810/280-10-50-26C

Reference 21: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 26B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-26B

Reference 22: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 40
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-40

Reference 23: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org/280/tableOfContent

Reference 24: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 26
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-26

Reference 25: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 41
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-41

+ Details

Employee Benefit Plans - Narrative (Details) $ in Millions	12 Months Ended
Employee Benefit Plans - Narrative (Details) $ in Millions	Dec. 31, 2025 USD ($) shares	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
Employee Benefit Plans [Line Items]
Accumulated Benefit Obligation for Pension Plan	$ 82.5	$ 80.8
Benefits plan assumed annual rate	8.00%
Increase declining annual rate	0.15%
Capital cost of covered healthcare benefits	5.00%
Employees plan	1,000
Contributions plan rate	100.00%
Stock based compensation remain award rate	1.00%
Compensation plus rate	50.00%
Contributions exceeding rate	1.00%
Matching contributions, percent	6.00%
Matching contributions	$ 0.9	0.8	$ 0.7
Discretionary contribution	$ 1.3	$ 1.1	$ 0.9
Compensation eligible rate	5.00%
Number of shares authorized (in Shares) \| shares	300,000
Percentage of shares available for issuance	62.00%
Restricted Stock Units \| Minimum
Employee Benefit Plans [Line Items]
Award forfeiture period upon termination of employment	3 years
Restricted Stock Units \| Maximum
Employee Benefit Plans [Line Items]
Award forfeiture period upon termination of employment	5 years
Pension Plan
Employee Benefit Plans [Line Items]
Expected cash contributions over next fiscal year	$ 0.9
Other Postretirement Benefits Plan
Employee Benefit Plans [Line Items]
Expected cash contributions over next fiscal year	$ 1.1

Income Taxes - Narrative (Details)	12 Months Ended
Income Taxes - Narrative (Details)	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Effective Income Tax Rate Reconciliation [Line Items]
Effective tax rate	10.10%	13.50%	3.20%
State corporate net income tax rates	2.70%
Minimum
Effective Income Tax Rate Reconciliation [Line Items]
State corporate net income tax rates	8.25%	8.25%	8.25%
Maximum
Effective Income Tax Rate Reconciliation [Line Items]
State corporate net income tax rates	9.00%	9.00%	9.00%

Short-term Borrowings (Tables)

12 Months Ended

Dec. 31, 2025

Short-Term Debt [Abstract]

Schedule of Short-Term Borrowings

Information regarding the Company’s short-term borrowings for the years ended December 31, 2025 and 2024 is summarized below:


	($ In Millions)
	2025			2024
Average Amount Outstanding	$	42.1		$	38.7
Weighted Average Interest Rate	5.42		%	6.33		%
Notes Payable at Year-End	$	28.3		$	23.0
Weighted Average Interest Rate at Year-End	5.03		%	5.63		%

Schedule of Lines of Credit


	(In Millions)
	As of December 31, 2025							Line of Credit Expiration Date
	Outstanding		Available		Maximum		Credit Type
Bank of America	$	—	$	60.0	$	60.0	Uncommitted	July 31, 2026
PNC Bank	9.3		58.7		68.0		Committed	January 31, 2027
CoBank, ACB (CoBank)	19.0		1.0		20.0		Committed	May 20, 2028
	$	28.3	$	119.7	$	148.0

Organization, Summary of Significant Accounting Policies and Recent Developments (Tables)

12 Months Ended

Dec. 31, 2025

Accounting Policies [Abstract]

Schedule of Range of Depreciation Rates for the Major Utility Plant Categories

The following table sets forth the range of depreciation rates for the major utility plant categories used to calculate depreciation for the years ended December 31, 2025, 2024, and 2023. These rates have been approved by the NJBPU or DEPSC:


Source of Supply	1.15% - 3.44%	Transmission and Distribution (T&D):
Pumping	2.00% - 5.39%	T&D – Mains	1.10% - 3.13%
Water Treatment	1.65% - 7.09%	T&D – Services	2.12% - 3.16%
General Plant	2.08% - 17.84%	T&D – Other	1.61% - 4.63%
Wastewater Collection	1.42% - 1.81%

Schedule of AFUDC Rates for Middlesex and Tidewater

The AFUDC rates for the years ended December 31, 2025, 2024 and 2023 for Middlesex and Tidewater are as follows:


	2025		2024		2023
Middlesex	6.64	%	6.64	%	6.35	%
Tidewater	7.04	%	7.92	%	7.92	%

Schedule of Operating Revenues

The Company’s operating revenues are comprised of the following:


	(In Thousands)
	Years Ended December 31,
	2025		2024		2023
Regulated Tariff Sales
Residential	$	102,437	$	97,802	$	86,581
Commercial	30,436		31,833		23,945
Industrial	13,367		13,842		11,586
Fire Protection	15,116		14,188		12,582
Wholesale	20,702		21,003		19,117
Non-Regulated Contract Operations	12,504		13,085		12,320
Total Revenue from Contracts with Customers	$	194,562	$	191,753	$	166,131
Other Regulated Revenues	596		691		806
Other Non-Regulated Revenues	481		467		453
Inter-segment Elimination	(945)		(1,034)		(1,116)
Total Revenue	$	194,694	$	191,877	$	166,274

Schedule of Issued Accounting Standards

The recently issued accounting standards and their impact on the Company as of December 31, 2025 are as follows:

Standard

Description

Date of Adoption

Application

Effect on the
Condensed
Consolidated
Financial Statements

Accounting Standards Update (ASU) 2023-09 “Improvements to Income Tax Disclosures”

The ASU is effective for the Company beginning with its annual financial statements for the year ending December 31, 2025.

Prospective, with retrospective application also permitted.

ASU 2024-03 “Disaggregation of Income Statement Expenses”

The ASU is effective for the Company beginning with its annual financial statements for the year ending December 31, 2027.

Prospective, with retrospective application also permitted.

The Company is currently evaluating the requirements of ASU 2024-03.

ASU 2025-06 "Internal-Use Software"

The ASU is effective for the Company beginning with its annual financial statements for the year ending December 31, 2028.

Prospective, with a modified transition or retrospective application also permitted.

The Company is evaluating the impact of ASU 2025-06 on its Consolidated Financial Statements and the timing of adoption.

CONSOLIDATED STATEMENTS OF COMMON STOCKHOLDERS' EQUITY - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Retained Earnings
Balance at beginning of period (in shares) at Dec. 31, 2022		17,642
Balance at beginning of period at Dec. 31, 2022	$ 400,328	$ 233,054	$ 167,274
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income	31,524		31,524
Dividend Reinvestment & Common Stock Purchase Plan (in shares)		167
Dividend Reinvestment & Common Stock Purchase Plan	12,115	$ 12,115
Restricted Stock Award - Net - Employees (in shares)		7
Restricted Stock Award - Net - Employees	1,235	$ 1,235
Stock Award - Board Of Directors (in shares)		5
Stock Award - Board Of Directors	360	$ 360
Common Stock Issuance Expenses	(10)		(10)
Cash Dividends on Common Stock	(22,441)		(22,441)
Cash Dividends on Preferred Stock	(120)		(120)
Balance at end of period (in shares) at Dec. 31, 2023		17,821
Balance at end of period at Dec. 31, 2023	422,991	$ 246,764	176,227
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income	44,351		44,351
Dividend Reinvestment & Common Stock Purchase Plan (in shares)		17
Dividend Reinvestment & Common Stock Purchase Plan	974	$ 974
Restricted Stock Award - Net - Employees (in shares)		(10)
Restricted Stock Award - Net - Employees	(383)	$ (383)
Stock Award - Board Of Directors (in shares)		8
Stock Award - Board Of Directors	398	$ 398
Cash Dividends on Common Stock	(23,408)		(23,408)
Cash Dividends on Preferred Stock	(109)		(109)
Conversion of $7 Preferred Stock to Common Stock (in shares)		51
Conversion of $7 Preferred Stock to Common Stock	$ 449	$ 449
Balance at end of period (in shares) at Dec. 31, 2024	17,887	17,887
Balance at end of period at Dec. 31, 2024	$ 445,263	$ 248,202	197,061
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income	42,822		42,822
Dividend Reinvestment & Common Stock Purchase Plan (in shares)		17
Dividend Reinvestment & Common Stock Purchase Plan	907	$ 907
Restricted Stock Award - Net - Employees (in shares)		18
Restricted Stock Award - Net - Employees	462	$ 462
Stock Award - Board Of Directors (in shares)		6
Stock Award - Board Of Directors	405	$ 405
At-The-Market Program Common Stock Issuance (in shares)		560
At-The-Market Program Common Stock Issuance	29,547	$ 29,547
Common Stock Issuance Expenses	(667)	$ (667)
Cash Dividends on Common Stock	(24,924)		(24,924)
Cash Dividends on Preferred Stock	(76)		(76)
Conversion of $7 Preferred Stock to Common Stock (in shares)		33
Conversion of $7 Preferred Stock to Common Stock	$ 292	$ 292
Balance at end of period (in shares) at Dec. 31, 2025	18,521	18,521
Balance at end of period at Dec. 31, 2025	$ 494,031	$ 279,148	$ 214,883

Commitments and Contingent Liabilities

12 Months Ended

Dec. 31, 2025

Commitments and Contingencies Disclosure [Abstract]

Commitments and Contingent Liabilities

Water Supply – Middlesex’s agreement with the New Jersey Water Supply Authority (NJWSA) for the purchase of untreated water expires November 30, 2048. NJSWA provides for an average purchase of 27.0 million gallons a day (mgd), with a peak up to 47.0 mgd. Pricing is set annually by the NJWSA through a public rate making process. The agreement has provisions for additional pricing in the event Middlesex overdrafts or exceeds certain monthly and annual thresholds.

Middlesex also has an agreement with a non-affiliated NJBPU-regulated water utility for the purchase of treated water. This agreement, which expires February 27, 2031, provides for the minimum purchase of 3.0 mgd of treated water with provisions for additional purchases if needed.

Tidewater contracts with the City of Dover, Delaware to purchase treated water of up to 75.0 million gallons annually.

Purchased water costs are shown below:


	(In Millions)
	Years Ended December 31,
	2025		2024		2023
Untreated	$	3.6	$	3.5	$	3.2
Treated	4.4		4.0		5.3
Total Costs	$	8.0	$	7.5	$	8.5

Leases - The Company determines if an arrangement is a lease at the inception of the lease. Generally, a lease agreement exists if the Company determines that the arrangement gives the Company control over the use of an identified asset and obtains substantially all of the benefits from the identified asset.

The Company has entered into an operating lease of office space for administrative purposes, expiring in December 2029. The Company has not entered into any finance leases. The exercise of a lease renewal option for the Company’s administrative offices is solely at the discretion of the Company.

The right-of-use (ROU) asset recorded represents the Company’s right to use an underlying asset for the lease term and lease liability represents the Company’s obligation to make lease payments arising from the lease. Lease ROU assets and liabilities are recognized at commencement date based on the present value of lease payments over the lease term. The Company’s operating lease does not provide an explicit discount rate and as such the Company used an estimated incremental borrowing rate (4.03%) based on the information available at commencement date in determining the present value of lease payments.

Given the impacts of accounting for regulated operations, and the resulting recognition of expense at the amounts recovered in customer rates, expenditures for operating leases are consistent with lease expense and was $0.8 million for each of the years ended December 31, 2025, 2024 and 2023.

Information related to operating lease ROU assets is as follows:


	(In Millions)
	December 31,
	2025		2024
ROU Asset at Lease Inception	$	7.3	$	7.3
Accumulated Amortization	(5.3)		(4.7)
Current ROU Asset	$	2.0	$	2.6

The Company’s future minimum operating lease commitments as of December 31, 2025 are as follows:


	(In Millions)
	December 31, 2025
2026	$	0.8
2027	0.9
2028	0.9
2029	0.9
2030	—
Total Lease Payments	$	3.5
Imputed Interest	(1.1)
Present Value of Lease Payments	2.4
Less Current Portion*	(0.6)
Non-Current Lease Liability	$	1.8

*Included in Other Current Liabilities

Construction – In connection with the Company’s planned capital expenditures, the Company has entered into several contractual construction agreements that in total obligate it to expend an estimated $21 million in the future. The actual

amount and timing of capital expenditures is dependent on the need for replacement of existing infrastructure, customer growth, residential new home construction and sales, project scheduling, supply chain issues and continued refinement of project scope and costs.

Contingencies – Based on our operations in the heavily-regulated water and wastewater industries, the Company is routinely involved in disputes, claims, lawsuits and other regulatory and legal matters, including responsibility for fines and penalties relative to regulatory compliance. At this time, Management does not believe the final resolution of any such matters, whether asserted or unasserted, will have a material adverse effect on the Company’s financial position, results of operations or cash flows. In addition, the Company maintains business insurance coverage that may mitigate the effect of current or future loss contingencies.

Change in Control Agreements – The Company has Change in Control Agreements with its executive officers that provide compensation and benefits in the event of termination of employment in connection with a change in control of the Company.

Organization, Summary of Significant Accounting Policies and Recent Developments - Schedule of Operating Revenues (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Disaggregation of Revenue [Line Items]
Total Revenue	$ 194,694	$ 191,877	$ 166,274
Operating Segments
Disaggregation of Revenue [Line Items]
Total Revenue from Contracts with Customers	194,562	191,753	166,131
Other Regulated Revenues	596	691	806
Other Non-Regulated Revenues	481	467	453
Total Revenue	195,639	192,911	167,390
Operating Segments \| Unregulated Service Contracts
Disaggregation of Revenue [Line Items]
Total Revenue from Contracts with Customers	12,504	13,085	12,320
Operating Segments \| Residential \| Regulated Tariff-Based Services
Disaggregation of Revenue [Line Items]
Total Revenue from Contracts with Customers	102,437	97,802	86,581
Operating Segments \| Commercial \| Regulated Tariff-Based Services
Disaggregation of Revenue [Line Items]
Total Revenue from Contracts with Customers	30,436	31,833	23,945
Operating Segments \| Industrial \| Regulated Tariff-Based Services
Disaggregation of Revenue [Line Items]
Total Revenue from Contracts with Customers	13,367	13,842	11,586
Operating Segments \| Fire Protection \| Regulated Tariff-Based Services
Disaggregation of Revenue [Line Items]
Total Revenue from Contracts with Customers	15,116	14,188	12,582
Operating Segments \| Wholesale \| Regulated Tariff-Based Services
Disaggregation of Revenue [Line Items]
Total Revenue from Contracts with Customers	20,702	21,003	19,117
Inter-segment Elimination
Disaggregation of Revenue [Line Items]
Total Revenue	$ (945)	$ (1,034)	$ (1,116)

Employee Benefit Plans - Schedule of Expected Benefit Payments (Details) $ in Thousands	Dec. 31, 2025 USD ($)
Pension Plan
Liability for Future Policy Benefit, Activity [Line Items]
2026	$ 5,446
2027	5,466
2028	5,588
2029	5,586
2030	5,691
2030-2034	30,481
Totals	58,258
Other Benefits Plan
Liability for Future Policy Benefit, Activity [Line Items]
2026	1,355
2027	1,427
2028	1,491
2029	1,593
2030	1,654
2030-2034	9,549
Totals	$ 17,070

Capitalization

12 Months Ended

Dec. 31, 2025

Equity [Abstract]

Capitalization

Common Stock

The Company issues shares of its common stock in connection with its Middlesex Water Company Investment Plan (the Investment Plan), a direct share purchase and dividend reinvestment plan for the Company’s common stock. The Company raised approximately $0.9 million under the Investment Plan during 2025. Currently, 0.7 million shares remain registered

with the United States Securities and Exchange Commission and available for issuance to participants under the Investment Plan.

In April 2023, the NJBPU authorized Middlesex to issue and sell up to 1.0 million shares of its common stock, without par value, for the period from April 2023 through December 2025, through one or more traditional underwriting offerings and/or At-the-Market (ATM) offerings. In September 2025, the NJBPU authorized Middlesex to issue and sell up to 2.5 million shares of its common stock, without par value, during the period January 2026 through December 2028, through one or more traditional underwriting offerings and/or ATM offerings. Sales of additional shares of common stock are part of the Company’s comprehensive financing plan to fund its multi-year utility plant infrastructure investment program. As described below in “Long-term Debt”, the NJBPU also approved the debt funding component of the financing plan.

On May 12, 2025, Middlesex entered into an ATM Equity Offering Sales Agreement (Equity Sales Agreement) with BofA Securities, Inc., Robert W. Baird & Co. Incorporated, and Janney Montgomery Scott LLC, pursuant to which Middlesex may offer and sell shares of its common stock, no par value per share, from time to time in “at-the-market” offerings, having an aggregate gross sales price of up to $110.0 million. The Company intends to use the net proceeds from these sales, after deducting commissions and offering expenses, to fund our capital expenditures, to purchase and maintain plant equipment, as well as for other general corporate purposes. For the year ended December 31, 2025, Middlesex issued and sold a total of 560,000 shares of common stock at a weighted average price of $53.54 per share, and received $29.5 million in net proceeds under the Equity Sales Agreement. As of December 31, 2025, the Company has $80.0 million of aggregate gross sales remaining under the Equity Sales Agreement.

The Company issues common shares under a restricted stock plan for certain management employees, which is described in Note 7 – Employee Benefit Plans.

The Company maintains a stock plan for its independent Directors as a component of outside members of the Board of Directors compensation. For the years ended December 31, 2025, 2024 and 2023, 6,318, 7,570 and 4,608 shares, respectively, of Middlesex common stock were granted and issued to the Company’s independent Directors under the plan. The maximum number of shares authorized for grant under the plan is 100,000, of which 27,965 shares remain available for future awards.

In the event dividends on the preferred stock are in arrears, no dividends may be declared or paid on the common stock of the Company.

Preferred Stock

At December 31, 2025, there were 120,000 shares of preferred stock authorized and less than 13,000 shares of preferred stock outstanding. There were no preferred stock dividends in arrears.

The Company may not pay any dividends on its common stock unless full cumulative dividends to the preceding dividend date for all outstanding shares of preferred stock have been paid or set aside for payment. If four or more quarterly dividends are in arrears, the preferred shareholders, as a class, are entitled to elect two members to the Board of Directors in addition to Directors elected by holders of the common stock. In addition, if Middlesex were to liquidate, holders of preferred stock would be paid back the stated value of their preferred shares before any distributions could be made to common stockholders.

The conversion feature of the no par $7.00 Series Cumulative and Convertible Preferred Stock allows the security holders to convert one convertible preferred share for twelve shares of the Company's common stock. In 2025, 2,782 shares of the Company’s no par $7.00 Series Cumulative and Convertible Preferred Stock were converted into 33,384 shares (approximately $0.3 million) of the Company’s common stock. In addition, the Company may redeem up to 10% of the outstanding convertible stock in any calendar year at a price equal to the fair value of twelve shares of the Company's common stock for each share of convertible stock redeemed.

Long-term Debt

Subject to regulatory approval, the Company periodically issues long-term debt to fund its investments in utility plant. To the extent possible and fiscally prudent, the Company finances qualifying capital projects under State Revolving Fund (SRF) loan programs in New Jersey and Delaware. These government programs provide financing at interest rates typically below rates available in the broader financial markets.

In September 2025, the NJBPU authorized Middlesex to borrow up to $260.0 million during the period January 2026 through December 2028, in one or more negotiated transactions in the form of notes and/or first mortgage bonds (FMBs) through loans from the New Jersey SRF Program, the New Jersey Economic Development Authority, private placement and other financial institutions as needed. Middlesex was previously authorized to borrow up to $300.0 million for the period beginning in April 2023 through December 2025.

In October 2025, Middlesex closed on a $30.0 million, 5.99% private placement of First Mortgage Bonds (FMBs) due 2055, designated as Series 2025A. The net proceeds from the sale were used to repay short-term borrowings under the Company’s bank lines of credit and for other general corporate purposes.

In September 2024, Tidewater closed on a $2.2 million Delaware SRF loan with a 0.0% interest rate with an expected maturity date in 2044. This loan is for costs associated with Tidewater’s obligation, as required by federal law and Delaware regulations, to identify and inventory lead service lines throughout Tidewater’s service area. Tidewater has drawn down $1.8 million as of December 31, 2025.

In May 2024, Tidewater closed on four DEPSC-approved Delaware SRF loans totaling $5.6 million, all at interest rates of 2.0% with maturity dates in 2045. These loans are for the construction, relocation, improvement, and/or interconnection of transmission mains and construction of a water treatment facility. In December 2025, Tidewater closed on an additional $1.0 million, 2.0% SRF loan with a maturity date of 2045 related to these projects. Tidewater has drawn down $0.9 million on these loans as of December 31, 2025. Each project has its own construction timetable with the last spending set to occur in 2027.

Separately, Tidewater has two active construction projects funded by Delaware SRF loans totaling $8.3 million with remaining availability of funds for borrowing. These loans are for the construction of a one million gallon elevated storage tank and construction, relocation, improvement, and interconnection of transmission mains. Tidewater has drawn a total of $7.1 million through December 31, 2025 and expects that the requisitions will continue through the first quarter of 2026.

In December 2025, Southern Shores closed on a $0.4 million Delaware SRF loan with a 0.0% interest rate with a maturity date in 2045. This loan is for costs associated with Southern Shore’s obligation, as required by federal law and Delaware regulations, to identify and inventory lead service lines in its' service area.

In February 2026, Pinelands Water and Pinelands Wastewater repaid in full $3.7 million and $3.4 million, respectively, of their amortizing secured notes. The interest rates and due dates on both of these notes were 6.17% and 2043, respectively.

The aggregate annual principal repayment obligations as of December 31, 2025 for all long-term debt over the next five years and thereafter are shown below:


Year	(In Millions) Annual Maturities

2026	$	7.9
2027	7.5
2028	7.2
2029	6.7
2030	5.8
Thereafter	350.8

The weighted average interest rate on all long-term debt at December 31, 2025 and 2024 was 3.49% and 3.64%, respectively.

Substantially all of the utility plant of the Company is subject to the lien of its mortgage, which includes debt service and capital ratio covenants. The Company is in compliance with all of its mortgage covenants and restrictions.

Earnings Per Share


	(In Thousands, Except Per Share Amounts)
	2025			2024			2023
Basic:	Income		Shares	Income		Shares	Income		Shares
Net Income	$	42,822	18,096	$	44,351	17,842	$	31,524	17,732
Preferred Dividend	(76)			(112)			(120)
Earnings Applicable to Common Stock	$	42,746	18,096	$	44,239	17,842	$	31,404	17,732
Basic EPS	$	2.36		$	2.48		$	1.77
Diluted:
Earnings Applicable to Common Stock	$	42,746	18,096	$	44,239	17,842	$	31,404	17,732
Convertible Preferred $7.00 Series Dividend	24		41	46		104	67		115
Adjusted Earnings Applicable to Common Stock	$	42,770	18,137	$	44,285	17,946	$	31,471	17,847
Diluted EPS	$	2.36		$	2.47		$	1.76

Fair Value of Financial Instruments

The following methods and assumptions were used by the Company in estimating its fair value disclosure for financial instruments for which it is practicable to estimate that value. The carrying amounts reflected in the consolidated balance sheets for cash and cash equivalents, accounts receivable, accounts payable and notes payable approximate their respective fair values due to the short-term maturities of these instruments. The fair value of FMBs and SRF Bonds (collectively, the Bonds) issued by Middlesex is based on quoted market prices for similar issues. Under the fair value hierarchy, the fair value of cash and cash equivalents is classified as a Level 1 measurement and the fair value of notes payable and the Bonds in the table below are classified as Level 2 measurements. The carrying amount and fair value of the Bonds were as follows:


	(In Thousands)
	At December 31,
	2025				2024
	Carrying Amount		Fair Value		Carrying Amount		Fair Value
FMBs	$	126,172	$	120,430	$	129,602	$	125,067

It was not practicable to estimate the fair value on our outstanding long-term debt for which there is no quoted market price and there is not an active trading market. For details, including carrying value, interest rate and due date on these series of long-term debt, please refer to those series of long-term debt titled “Amortizing Secured Notes” and “State Revolving Trust Notes” on the Consolidated Statements of Capital Stock and Long-Term Debt. The carrying amount of these instruments was $259.5 million and $229.8 million at December 31, 2025 and 2024, respectively. Advances for construction have carrying amounts of $25.5 million and $22.6 million at December 31, 2025 and 2024, respectively. Their relative fair values cannot be accurately estimated since future refund payments depend on several variables, including new customer connections, customer consumption levels and future rate increases.

- Definition

The entire disclosure for equity.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 8A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-8A

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-13

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-13

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
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+ Details

Income Taxes - Schedule of Components of Income Tax Expense (Benefit) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Current:
Federal	$ 2,971	$ 1,554	$ 2,952
State	1,292	1,126	1,066
Deferred:
Federal	295	3,802	(3,261)
State	317	482	348
Investment Tax Credits	(54)	(59)	(64)
Total Income Tax Expense	$ 4,821	$ 6,905	$ 1,041

- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

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+ Details

Audit Information	12 Months Ended
Audit Information	Dec. 31, 2025	Dec. 31, 2024
Audit Information [Abstract]
Auditor Name	PricewaterhouseCoopers LLP	Baker Tilly US, LLP
Auditor Location	New York, New York	Philadelphia, Pennsylvania
Auditor Firm ID	238	23

Supplemental Cash Flows Information

12 Months Ended

Dec. 31, 2025

Supplemental Cash Flow Elements [Abstract]

Supplemental Cash Flows Information


(in thousands)	2025		2024		2023
SUPPLEMENTAL DISCLOSURE OF NON-CASH ACTIVITY:
Utility Plant received as Construction Advances and Contributions	$	9,924	$	8,968	$	7,259
Accrued Payables for Utility Plant	9,901		8,109		10,251
Litigation Settlement Receivable	—		(6,237)		69,872
Litigation Settlement Payable	—		(6,237)		6,237
Conversion of Preferred Stock Into Common Stock	292		449		—

SUPPLEMENTAL DISCLOSURE OF CASH FLOWS INFORMATION:
Cash Paid During the Year for:
Interest	13,459		14,485		12,762
Interest Capitalized	640		511		975
Income Taxes	1,639		3,169		2,962

The cash flow impact of Tangible Property Repairs in Note 3, Income Taxes is reflected in Provision for Deferred Income Taxes and Investment Tax Credits in the Consolidated Statements of Cash Flows.

Rates and Regulatory Matters (Tables)

12 Months Ended

Dec. 31, 2025

Regulated Operations [Abstract]

Schedule of Unamortized Balances

These items are detailed as follows:


	(In Thousands)
	December 31,
Regulatory Assets	2025		2024
Income Taxes (a)	$	97,300	$	89,825
Other (b)	12,984		11,958
Total	$	110,284	$	101,783

Regulatory Liabilities
Income Taxes (c)	$	25,585	$	27,380
Cost of Removal (d)	22,037		20,595
Employee Benefit Plans (e)	11,526		9,435
Lawsuit Settlement (f)	1,598		5,334
New Jersey Revenue Taxes (g)	3,258		1,813
MDL Settlement (h)	$	4,433	$	—
Total	$	68,437	$	64,557

(a)The recovery period for income taxes is dependent upon when the temporary differences between the tax and book treatment of various items reverse.

(b)Other primarily includes deferred costs for rate cases and tank painting.

(f)The net proceeds available to Middlesex from the 3M Settlement Agreement were recorded as a regulatory liability and are being used for future related operating and maintenance costs.

Rates and Regulatory Matters - Narrative (Details) $ in Millions			1 Months Ended								6 Months Ended		12 Months Ended		18 Months Ended
	Jan. 01, 2026 USD ($)	Jan. 01, 2025 USD ($)	Feb. 19, 2026 USD ($)	Jan. 31, 2026 USD ($) entity customer	Dec. 31, 2025 USD ($)	Nov. 30, 2025 USD ($)	Jul. 31, 2025 USD ($)	Apr. 30, 2025 USD ($) customer	Feb. 28, 2025 USD ($)	Sep. 30, 2024 USD ($)	Dec. 31, 2025 USD ($)	Jun. 30, 2025 USD ($)	Dec. 31, 2025 USD ($) unit	Dec. 31, 2024 USD ($)	Dec. 31, 2025 USD ($)
DSIC
Rate and Regulatory Matters (Details) [Line Items]
Approved increase in annual operating revenues														$ 2.3
Tidewater \| Town of Ocean View Water Utility Assets
Rate and Regulatory Matters (Details) [Line Items]
Acquisition of assets								$ 4.6
Number of customers served \| customer								900
Subsequent Event \| Tidewater \| Pinewood Acres Water Utility Assets
Rate and Regulatory Matters (Details) [Line Items]
Acquisition of assets				$ 0.2
Number of customers served \| customer				350
NJBPU \| DSIC
Rate and Regulatory Matters (Details) [Line Items]
Approved increase in annual operating revenues						$ 0.9
NJBPU \| PWAC
Rate and Regulatory Matters (Details) [Line Items]
Approved recovery of costs									$ 0.5
NJBPU \| LSLR
Rate and Regulatory Matters (Details) [Line Items]
Approved recovery of costs												$ 0.3			$ 0.3
NJBPU \| Subsequent Event
Rate and Regulatory Matters (Details) [Line Items]
Approved increase in annual operating revenues			$ 14.5
Return on equity			9.60%
Common equity ratio			54.25%
NJBPU \| Subsequent Event \| Middlesex And Pinelands Customers
Rate and Regulatory Matters (Details) [Line Items]
Refund credited amount			$ 3.3
NJBPU \| Subsequent Event \| Middlesex and Pinelands
Rate and Regulatory Matters (Details) [Line Items]
Number of entities approved for corporate reorganization \| entity				3
NJBPU \| Subsequent Event \| Middlesex and Pinelands \| RESIC
Rate and Regulatory Matters (Details) [Line Items]
Period for approved recovery of costs			3 years
Period for surcharge filings			6 months
Maximum value of costs to be recovered			$ 3.6
Maximum percentage of costs to be recovered			2.50%
NJBPU \| Subsequent Event \| Middlesex and Pinelands \| DSIC
Rate and Regulatory Matters (Details) [Line Items]
Period for approved recovery of costs			3 years
Period for surcharge filings			6 months
Maximum value of costs to be recovered			$ 7.1
Maximum percentage of costs to be recovered			5.00%
DEPSC \| Tidewater
Rate and Regulatory Matters (Details) [Line Items]
Approved increase in annual operating revenues							$ 5.5
Return on equity							9.50%
Common equity ratio							53.50%
Approved recovery of costs										$ 2.1
Refund of excess deferred income taxes											$ 1.1
Refund of interest on excess deferred income taxes											$ 0.4
Amount spent to identify and inventory lead service lines													$ 1.9
DEPSC \| Tidewater \| DSIC
Rate and Regulatory Matters (Details) [Line Items]
Approved increase in annual operating revenues					$ 0.3
DEPSC \| Southern Shores
Rate and Regulatory Matters (Details) [Line Items]
Approved increase in annual operating revenues		$ 0.1
Number of unit condominium community entity provides water service to \| unit													2,200
Increase in annual operating revenues		6.51%
DEPSC \| Southern Shores \| Minimum
Rate and Regulatory Matters (Details) [Line Items]
Increase in annual operating revenues													3.00%
DEPSC \| Subsequent Event \| Tidewater Customers
Rate and Regulatory Matters (Details) [Line Items]
Refund credited amount			$ 1.1
DEPSC \| Subsequent Event \| Southern Shores
Rate and Regulatory Matters (Details) [Line Items]
Approved increase in annual operating revenues	$ 0.1
Increase in annual operating revenues	4.89%

Employee Benefit Plans - Schedule of Effect of One-Percentage Point Change in Assumed Health Care Cost Trend Rates (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2025 USD ($)
Retirement Benefits [Abstract]
Effect on Current Year Service and Interest Costs, Increase	$ 295
Effect on Current Year Service and Interest Costs, Decrease	(239)
Effect on Projected Benefit Obligation, Increase	4,199
Effect on Projected Benefit Obligation, Decrease	$ (3,434)

Business Segment Data - Narrative (Details)	12 Months Ended
Business Segment Data - Narrative (Details)	Dec. 31, 2025 segment
Segment Reporting [Abstract]
Number of reportable segments	2

Organization, Summary of Significant Accounting Policies and Recent Developments - Schedule of AFUDC Rates for Middlesex and Tidewater (Details)	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Middlesex
Public Utilities, General Disclosures [Line Items]
Allowance for funds used during construction rates	6.64%	6.64%	6.35%
Tidewater
Public Utilities, General Disclosures [Line Items]
Allowance for funds used during construction rates	7.04%	7.92%	7.92%

Insider Trading Policies and Procedures	12 Months Ended
Insider Trading Policies and Procedures	Dec. 31, 2025
Insider Trading Policies and Procedures [Line Items]
Insider Trading Policies and Procedures Adopted	true

Commitments and Contingent Liabilities - Schedule of Operating Lease ROU Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Commitments and Contingencies Disclosure [Abstract]
ROU Asset at Lease Inception	$ 7,300	$ 7,300
Accumulated Amortization	(5,300)	(4,700)
Current ROU Asset	$ 1,972	$ 2,567

Organization, Summary of Significant Accounting Policies and Recent Developments - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Organization, Summary Of Significant Accounting Policies And Recent Developments [Line Items]
Percentage of operating revenues	94.00%
Percentage of total assets	99.00%
Refunded CAC	$ 0.5
Allowance for credit losses	1.6	$ 2.7
Bad debt expense	0.3	1.6	$ 1.0
Accounts receivable write-offs	$ 1.4	$ 1.0	$ 1.2
Minimum
Organization, Summary Of Significant Accounting Policies And Recent Developments [Line Items]
Estimated useful lives	3 years
Maximum
Organization, Summary Of Significant Accounting Policies And Recent Developments [Line Items]
Estimated useful lives	42 years

Rates and Regulatory Matters - Schedule of Regulatory Assets and Liabilities (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024
Regulatory Asset
Regulatory Assets	$ 110,284	$ 101,783
Regulatory Liabilities
Regulatory Liabilities	$ 68,437	64,557
U.S Federal Statutory Tax Rate	21.00%
Maximum
Regulatory Liabilities
U.S Federal Statutory Tax Rate	35.00%
Minimum
Regulatory Liabilities
U.S Federal Statutory Tax Rate	21.00%
Income Taxes
Regulatory Liabilities
Regulatory Liabilities	$ 25,585	27,380
Cost of Removal
Regulatory Liabilities
Regulatory Liabilities	22,037	20,595
Employee Benefit Plans
Regulatory Liabilities
Regulatory Liabilities	11,526	9,435
Lawsuit Settlement
Regulatory Liabilities
Regulatory Liabilities	1,598	5,334
New Jersey Revenue Taxes
Regulatory Liabilities
Regulatory Liabilities	3,258	1,813
MDL Settlement
Regulatory Liabilities
Regulatory Liabilities	4,433	0
Income Taxes
Regulatory Asset
Regulatory Assets	97,300	89,825
Other Regulatory Assets
Regulatory Asset
Regulatory Assets	$ 12,984	$ 11,958

Short-Term Borrowings - Schedule of Lines of Credit (Details) - Line of Credit	Dec. 31, 2025 USD ($)
Line of Credit Facility [Line Items]
Outstanding	$ 28,300,000
Available	119,700,000
Maximum	148,000,000.0
Bank of America
Line of Credit Facility [Line Items]
Outstanding	0
Available	60,000,000.0
Maximum	60,000,000.0
PNC Bank
Line of Credit Facility [Line Items]
Outstanding	9,300,000
Available	58,700,000
Maximum	68,000,000.0
CoBank, ACB (CoBank)
Line of Credit Facility [Line Items]
Outstanding	19,000,000.0
Available	1,000,000.0
Maximum	$ 20,000,000.0

Employee Benefit Plans - Schedule of Employee Benefit Plans Recognized in Balance Sheet (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Current Liability	$ 883	$ 883
Noncurrent Asset	(15,854)	(12,030)
Net Asset Recognized	(14,971)	(11,147)
Other Benefits Plan
Defined Benefit Plan Disclosure [Line Items]
Current Liability	0	0
Noncurrent Asset	(28,474)	(24,826)
Net Asset Recognized	$ (28,474)	$ (24,826)

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (q)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-5

Reference 16: http://www.xbrl.org/2003/role/disclosureRef
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Reference 17: http://www.xbrl.org/2003/role/disclosureRef
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Reference 18: http://www.xbrl.org/2003/role/disclosureRef
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-SubTopic 20
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Reference 19: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
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Reference 20: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-5

+ Details

Income Taxes

12 Months Ended

Dec. 31, 2025

Income Tax Disclosure [Abstract]

Income Taxes

The following table is a reconciliation of the U.S. federal statutory rate of 21% to the Company’s effective rate for the year ended December 31, 2025 in accordance with the guidance in ASU No. 2023-09:


	($ in Thousands)
	Year Ended December 31, 2025
	$		%
Earnings from continuing operations, before income tax expense	$	47,643

U.S Federal Statutory Tax Rate	10,005		21.0	%
State Taxes, Net of Federal Income Tax Effect (*)	1,271		2.7	%
Nontaxable or Nondeductible Items
Utility Plant Related	(726)		(1.5)	%
Tangible Property Repairs	(5,792)		(12.2)	%
Other Adjustments	63		0.1	%
Total Income Tax Expense	$	4,821	10.1	%

(*) State taxes in Delaware make up the majority (greater than 50 percent) of the tax effect in this category.

The following table is a reconciliation of the U.S. federal statutory rate of 21% to the Company’s effective rate for the years ended December 31, 2024 and 2023 in accordance with the guidance prior to the adoption of ASU No. 2023-09:


	Years Ended December 31,
	2024		2023
Income Tax at Statutory Rate	$	10,764	$	6,839
Tax Effect of:
Utility Plant Related	(659)		(1,495)
Tangible Property Repairs	(4,535)		(5,475)
State Income Taxes-Net	1,270		1,117
Other	65		55
Total Income Tax Expense	$	6,905	$	1,041

The Company paid income taxes as follows:


	Year Ended
	December 31, 2025
Federal taxes Paid	$	236

State Taxes Paid-New Jersey	307
State Taxes Paid-Delaware	1,092
State Taxes Paid-Other	4
Total State Taxes Paid	$	1,403

Total Income Taxes Paid	$	1,639

The table above is in accordance with the guidance in ASU No. 2023-09.

The Company’s effective tax rate was 10.1%, 13.5% and 3.2% for the years ended December 31, 2025, 2024 and 2023, respectively.

The statutory Federal tax rate is 21.0% for the years ended December 31, 2025, 2024 and 2023. For states where the Company's subsidiaries are subject to a state income tax, the state corporate net income tax rates range from 8.25% to 9.0% for all periods presented. Our effective tax rate differs from the federal statutory tax rate primarily due to the recognition of the income tax benefits for the immediate deduction of repair expenditures on tangible property in the Middlesex System as well as other permanent book-to-tax differences.

Income tax expense (benefit) is comprised of the following:


	(In Thousands)
	Years Ended December 31,
	2025		2024		2023
Current:
Federal	$	2,971	$	1,554	$	2,952
State	1,292		1,126		1,066
Deferred:
Federal	295		3,802		(3,261)
State	317		482		348
Investment Tax Credits	(54)		(59)		(64)
Total Income Tax Expense	$	4,821	$	6,905	$	1,041

As part of Middlesex’s March 2018 general rate case settlement with the NJBPU, Middlesex received approval for regulatory accounting treatment of income tax benefits associated with the adoption of tangible property regulations issued by the IRS as well as prospective recognition of the income tax benefits for the immediate deduction of repair costs on tangible property. This results in significant reductions in the Company’s effective income tax rate, current income tax expense and deferred income tax expense (benefit).

Deferred income taxes reflect the net tax effect of temporary differences between the carrying amounts of assets and liabilities for financial purposes and the amounts used for income tax purposes. The components of the net deferred tax liability are as follows:


	(In Thousands)
	December 31,
	2025		2024
Utility Plant Related	$	100,934	$	95,877
Customer Advances	850		(3,525)
Employee Benefits	8,778		7,888
Investment Tax Credits	128		181
Other	(215)		814
Total Accumulated Deferred Income Taxes	$	110,475	$	101,235

The Company has no material unrecognized tax benefits, interest, or penalties and does not expect significant changes to unrecognized tax benefits within the next 12 months.

An IRS examination of the Company's 2023 federal income tax returns commenced in February 2026. The Company is also obligated to report adjustments resulting from IRS settlements to state tax authorities.

- Definition

The entire disclosure for income tax.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 740
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
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-URI https://asc.fasb.org/1943274/2147477617/942-740-50-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
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-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480738/235-10-S50-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478822/944-740-50-1

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org/1943274/2147482685/740-10-50-12

Reference 5: http://www.xbrl.org/2003/role/exampleRef
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
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Reference 10: http://www.xbrl.org/2003/role/disclosureRef
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Reference 11: http://www.xbrl.org/2003/role/disclosureRef
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Reference 12: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org/740/tableOfContent

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
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-Section 50
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-14

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-21

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-17

Reference 16: http://www.xbrl.org/2003/role/disclosureRef
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-Publisher FASB
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Reference 17: http://www.xbrl.org/2003/role/disclosureRef
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-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482603/740-30-50-2

+ Details

Short-term Borrowings - Schedule of Short-Term Borrowings (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024
Short-Term Debt [Line Items]
Notes Payable at Year-End	$ 28,250	$ 23,000
Line of Credit
Short-Term Debt [Line Items]
Average Amount Outstanding	$ 42,100	$ 38,700
Weighted Average Interest Rate	5.42%	6.33%
Notes Payable at Year-End	$ 28,300	$ 23,000
Weighted Average Interest Rate	5.03%	5.63%

Employee Benefit Plans

12 Months Ended

Dec. 31, 2025

Retirement Benefits [Abstract]

Employee Benefit Plans

Pension Benefits

The Company’s Pension Plan covers all active employees hired prior to April 1, 2007. Employees hired after March 31, 2007 are not eligible to participate in this plan, but can participate in a defined contribution profit sharing plan that provides an annual contribution at the discretion of the Company, based upon a percentage of the participants’ annual paid compensation. In order to be eligible for contribution, the eligible employee must be employed by the Company on December 31st of the year to which the contribution relates. The Company maintains an unfunded supplemental plan for a

limited number of its executive officers. The Accumulated Benefit Obligation for the Company’s Pension Plan at December 31, 2025 and 2024 was $82.5 million and $80.8 million, respectively.

Other Benefits

The Company’s Other Benefits Plan covers substantially all of its current retired employees. Employees hired after March 31, 2007 are not eligible to participate in this plan. Coverage includes healthcare and life insurance.

Regulatory Treatment of Over/Underfunded Retirement Obligations

Because the Company is subject to rate regulation in the states in which it operates, it is required to maintain its accounts in accordance with the regulatory authority’s rules and guidelines, which may differ from other authoritative accounting pronouncements. In those instances, the Company follows the guidance of ASC 980, Regulated Operations. Based on prior regulatory practice, and in accordance with the guidance in ASC 980, Regulated Operations, the Company records underfunded Pension Plan and Other Benefits Plan obligation costs, which otherwise would be recognized in Other Comprehensive Income under ASC 715, Compensation – Retirement Benefits, as a Regulatory Asset, and expects to recover those costs in rates charged to customers. The Company uses a December 31 measurement date for all of its employee benefit plans. The tables below set forth information relating to the Company’s Pension Plan and Other Benefits Plan for 2025 and 2024.


	(In Thousands)
	Pension Plan				Other Benefits Plan
	Years Ended December 31,
	2025		2024		2025		2024
Change in Projected Benefit Obligation:
Beginning Balance	$	87,501	$	91,853	$	28,201	$	28,000
Service Cost	967		1,270		340		320
Interest Cost	4,635		4,280		1,719		1,313
Actuarial (Gain) Loss	1,026		(5,478)		2,867		(486)
Benefits Paid	(5,079)		(4,424)		(1,102)		(946)
Ending Balance	$	89,050	$	87,501	$	32,025	$	28,201


	(In Thousands)
	Pension Plan				Other Benefits Plan
	Years Ended December 31,
	2025		2024		2025		2024
Change in Fair Value of Plan Assets:
Beginning Balance	$	98,648	$	92,346	$	53,027	$	48,352
Actual Return on Plan Assets	9,566		7,976		7,473		4,675
Employer Contributions	886		2,750		1,102		946
Benefits Paid	(5,079)		(4,424)		(1,102)		(946)
Ending Balance	$	104,021	$	98,648	$	60,500	$	53,027

Funded Status	$	14,971	$	11,147	$	28,474	$	24,826


	(In Thousands)
	Pension Plan				Other Benefits Plan
	As of December 31,
	2025		2024		2025		2024
Amounts Recognized in the Consolidated
Balance Sheets consist of:
Current Liability	$	883	$	883	$	—	$	—
Noncurrent Asset	(15,854)		(12,030)		(28,474)		(24,826)
Net Asset Recognized	$	(14,971)	$	(11,147)	$	(28,474)	$	(24,826)


	(In Thousands)
	Pension Plan						Other Benefits Plan
	Years Ended December 31,
	2025		2024		2023		2025		2024		2023
Components of Net Periodic Benefit (Gain) Cost
Service Cost	$	967	$	1,270	$	1,551	$	340	$	320	$	391
Interest Cost	4,635		4,280		4,270		1,719		1,313		1,608
Expected Return on Plan Assets	(6,748)		(6,322)		(5,865)		(3,712)		(3,384)		(3,082)
Amortization of Net Actuarial Loss (Gain)	50		153		658		(613)		(1,098)		(191)
Net Periodic Benefit (Gain) Cost*	$	(1,096)	$	(619)	$	614	$	(2,266)	$	(2,849)	$	(1,274)

*Service cost is included in Operations and Maintenance expense on the consolidated statements of income; all other amounts are included in Other Income, net.

Amounts that are expected to be amortized from Regulatory Assets into Net Periodic Benefit Cost in 2025 are as follows:


	(In Thousands)
	Pension Plan		Other Benefits Plan
Actuarial Loss (Gain)	$	74	$	(1,071)


	Pension Plan						Other Benefits Plan
	2025		2024		2023		2025		2024		2023
Weighted Average Assumptions:
Expected Return on Plan Assets for:
Benefit Cost	7.00	%	7.00	%	7.00	%	7.00	%	7.00	%	7.00	%
Discount Rate for:
Benefit Obligation	5.39	%	5.47	%	4.79	%	5.49	%	5.49	%	4.79	%
Benefit Cost	5.47	%	4.79	%	4.98	%	5.49	%	4.79	%	4.98	%
Compensation Increase for:
Benefit Obligation	3.00	%	3.00	%	3.00	%	3.00	%	3.00	%	3.00	%
Benefit Cost	3.00	%	3.00	%	3.00	%	3.00	%	3.00	%	3.00	%

The compensation increase assumption for the Other Benefits Plan is attributable to life insurance provided to qualifying employees upon their retirement. The insurance coverage will be determined based on the employee’s base compensation as of their retirement date.

The Company utilizes the Society of Actuaries’ mortality table (Pri-2012) (Mortality Improvement Scale MP2021).

For the 2025 valuation, costs and obligations for our Other Benefits Plan assumed a 8.0% annual rate of increase in the per capita cost of covered healthcare benefits in 2026 with the annual rate of increase declining 0.15% per year for 2027-2046, resulting in an annual rate of increase in the per capita cost of covered healthcare benefits of 5.0% by year 2046.

A one-percentage point change in assumed healthcare cost trend rates would have the following effects on the Other Benefits Plan:


	(In Thousands)
	1 Percentage Point
	Increase		Decrease
Effect on Current Year Service and Interest Costs	$	295	$	(239)
Effect on Projected Benefit Obligation	$	4,199	$	(3,434)

The following benefit payments, which reflect expected future service, are expected to be paid:


	(In Thousands)
Year	Pension Plan		Other Benefits Plan
2026	$	5,446	$	1,355
2027	5,466		1,427
2028	5,588		1,491
2029	5,586		1,593
2030	5,691		1,654
2030-2034	30,481		9,549
Totals	$	58,258	$	17,070

Benefit Plans Assets

The allocation of plan assets at December 31, 2025 and 2024 by asset category is as follows:


	Pension Plan						Other Benefits Plan
Asset Category	2025		2024		Target		2025		2024		Target
Equity Securities	51.9	%	31.8	%	30	%	68.0	%	65.2	%	65	%
Debt Securities	47.5	%	67.9	%	68	%	30.0	%	33.0	%	33	%
Cash	0.6	%	0.3	%	2	%	2.0	%	1.8	%	2	%
Total	100.0	%	100.0	%			100.0	%	100.0	%

Two outside investment firms each manage a portion of the Pension Plan asset portfolio. One of those investment firms also manages the Other Benefits Plan asset portfolio. Quarterly meetings are held between the Company’s Pension Committee of the Board of Directors and the investment managers to review their performance and asset allocation. If the actual asset allocation is outside the targeted range, the Pension Committee reviews current market conditions and advice provided by the investment managers to determine the appropriateness of rebalancing the portfolio.

The objective of the Company is to maximize the long-term return on retirement plan assets, relative to a reasonable level of risk, maintain a diversified investment portfolio and maintain compliance with the Employee Retirement Income Security Act of 1974. The expected long-term rate of return is based on the various asset categories in which plan assets are invested and the current expectations and historical performance for these categories.

Fair Value Measurements

Accounting guidance provides a fair value hierarchy that prioritizes the inputs to valuation techniques used to measure fair value. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurements) and the lowest priority to unobservable inputs (Level 3 measurements). The three levels of the fair value hierarchy are described as follows:

•Level 1 – Inputs to the valuation methodology are unadjusted quoted market prices for identical assets or liabilities in accessible active markets.

•Level 2 – Inputs to the valuation methodology that are observable, either directly or indirectly, such as quoted prices for similar assets or liabilities; quoted prices in markets that are not active; or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities. If the asset or liability has a specified contractual term, the Level 2 input must be observable for substantially the full term of the asset or liability.

•Level 3 – Inputs to the valuation methodology are unobservable and significant to the fair value measurement.

Certain investments in cash and cash equivalents, equity securities, and commodities are valued based on quoted market prices in active markets and are classified as Level 1 investments. Certain investments in cash and cash equivalents, equity securities and fixed income securities are valued using prices received from pricing vendors that utilize observable inputs and are therefore classified as Level 2 investments.

The following tables present Middlesex’s Pension Plan assets measured and recorded at fair value within the fair value hierarchy:


	(In Thousands)
	As of December 31, 2025
	Level 1		Level 2		Level 3		Total
Money Market Funds	$	637	$	—	$	—	$	637
Government Treasury	21,546		—		—		21,546
Common Equity Securities	32,400		—		—		32,400
Corporate Bonds	—		44,878		—		44,878
Sovereign/Non-US Debt	—		4,560		—		4,560
Total Investments	$	54,583	$	49,438	$	—	$	104,021


	(In Thousands)
	As of December 31, 2024
	Level 1		Level 2		Level 3		Total
Mutual Funds	$	31,187	$	—	$	—	$	31,187
Money Market Funds	293		—		—		293
Common Equity Securities	195		—		—		195
Corporate Bonds	42,974		—		—		42,974
Agency/US Debt	19,041		—		—		19,041
Sovereign/Non-US Debt	4,958		—		—		4,958
Total Investments	$	98,648	$	—	$	—	$	98,648

The following tables present Middlesex’s Other Benefits Plan assets measured and recorded at fair value within the fair value hierarchy:


	(In Thousands)
	As of December 31, 2025
	Level 1		Level 2		Level 3		Total
Money Market Funds	885		—		—		885
Cash	317		—		—		317
Equity Securities	41,150		—		—		41,150
Agency/US/State/Municipal Debt	—		18,148		—		18,148
Total Investments	$	42,352	$	18,148	$	—	$	60,500


	(In Thousands)
	As of December 31, 2024
	Level 1		Level 2		Level 3		Total
Mutual Funds	$	34,545	$	—	$	—	$	34,545
Money Market Funds	977		—		—		977
Agency/US/State/Municipal Debt	—		17,505		—		17,505
Total Investments	$	35,522	$	17,505	$	—	$	53,027

Benefit Plans Contributions

For the Pension Plan, Middlesex expects to make approximately $0.9 million of cash contributions in 2026.

For the Other Benefits Plan, Middlesex expects to make approximately $1.1 million of cash contributions in 2026.

401(k) Plan

The Company maintains a 401(k) defined contribution plan, which covers substantially all employees (temporary employee needs to complete at least 1,000 hours of service to be eligible). Under the terms of the plan, the Company matches 100% of a participant’s contributions, which do not exceed 1% of a participant’s compensation, plus 50% of a participant’s contributions exceeding 1%, but not more than 6%. The Company’s matching contribution was $0.9 million, $0.8 million and $0.7 million for the years ended December 31, 2025, 2024 and 2023, respectively.

Employees hired after March 31, 2007 are not eligible to participate in the Pension Plan and are generally eligible to participate in a discretionary profit sharing plan administered through the 401(k) plan. In December each year, the Board of Directors may approve that a stated percentage of eligible compensation be contributed to the account of the employee participant in the first quarter of the following year. For those employees still actively employed on December 31, 2025 or retired during the current year, the Company will fund a discretionary contribution of $1.3 million before April 1, 2026, which represents 5.0% of eligible 2025 compensation. For the years ended December 31, 2024 and 2023, the Company made qualifying discretionary contributions of $1.1 million and $0.9 million respectively for each year.

Stock-Based Compensation

The Company maintains a long-term incentive compensation plan for certain management employees where awards are made in the form of restricted common stock. Shares of restricted stock issued under the plan are subject to forfeiture by the employee in the event of termination of employment for any reason within three or five years of the award, as applicable, other than as a result of retirement at normal retirement age, death, disability or change in control. The maximum number of shares authorized for award under the plan is 300,000 shares, of which approximately 62% remain available for issuance.

The Company recognizes compensation expense at fair value for the plan awards in accordance with ASC 718, Compensation – Stock Compensation. Compensation expense is determined by the market value of the stock on the date of the award and is being amortized over the expected vesting period.

The following table presents awarded but not yet vested share information for the plan:


	Shares(thousands)	Unearned Compensation (thousands)		Weighted Average Granted Price
Balance, January 1, 2021	83	$	1,931
Granted	11	1,151		$	105.17
Vested	(17)
Amortization of Compensation expense	—	(1,350)
Balance, December 31, 2022	77	1,732
Granted	15	1,165		$	77.63
Vested	(18)	—
Amortization of Compensation expense	—	(1,854)
Balance, December 31, 2023	74	1,043
Granted	19	1,003		$	52.50
Vested	(58)	—
Amortization of Compensation expense	—	(1,140)
Balance, December 31, 2024	35	906
Granted	24	1,540		$	64.10
Vested	(17)
Amortization of Compensation expense	—	(905)
Balance, December 31, 2025	42	1,541

- Definition

The entire disclosure for retirement benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (o)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (p)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Commitments and Contingent Liabilities - Schedule of Purchased Water Costs (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Direct Operating Costs [Abstract]
Untreated	$ 3,600	$ 3,500	$ 3,200
Treated	4,400	4,000	5,300
Total Costs	$ 7,994	$ 7,497	$ 8,481

Business Segment Data (Tables)

12 Months Ended

Dec. 31, 2025

Segment Reporting [Abstract]

Schedule of Inter-Segment Transactions


	(In Thousands)
	Years Ended December 31,
Operation by Segments	2025		2024		2023
Revenues:
Regulated	$	182,654	$	179,359	$	154,617
Non – Regulated	12,985		13,552		12,773
Total Reportable Segments	195,639		192,911		167,390
Inter-segment Elimination	(945)		(1,034)		(1,116)
Consolidated Revenues	$	194,694	$	191,877	$	166,274

Operating Expenses
Purchased Water:
Regulated	$	8,458	$	8,064	$	9,144
Non – Regulated	—		—		—
Total Reportable Segments	8,458		8,064		9,144
Inter-segment Elimination	(464)		(567)		(663)
Consolidated Purchased Water	$	7,994	$	7,497	$	8,481

Other Operations and Maintenance Expenses:
Regulated	$	75,293	$	76,483	$	66,670
Non – Regulated	8,485		8,850		8,415
Total Reportable Segments	83,778		85,333		75,085
Inter-segment Elimination	(481)		(467)		(453)
Consolidated Other Operations and Maintenance Expenses	$	83,297	$	84,866	$	74,632

Other Taxes:
Regulated	$	21,675	$	21,644	$	18,504
Non – Regulated	239		230		240
Consolidated Other Taxes	$	21,914	$	21,874	$	18,744

Depreciation:
Regulated	$	26,844	$	24,173	$	24,931
Non – Regulated	269		257		263
Consolidated Depreciation	$	27,113	$	24,430	$	25,194

Operating Income:
Regulated	$	50,865	$	49,462	$	35,820
Non – Regulated	3,511		3,748		3,403
Consolidated Operating Income	$	54,376	$	53,210	$	39,223

Other Income (Expense), Net:
Regulated	$	8,001	$	12,195	$	6,637
Non – Regulated	236		281		214
Total Reportable Segments	8,237		12,476		6,851
Inter-segment Elimination	(675)		(407)		(366)
Consolidated Other Income, Net	$	7,562	$	12,069	$	6,485


	(In Thousands)
	Years Ended December 31,
Operation by Segments (continued)	2025		2024		2023
Interest Expense:
Regulated	$	14,970	$	14,430	$	13,508
Non – Regulated	—		—		—
Total Reportable Segments	14,970		14,430		13,508
Inter-segment Elimination	(675)		(407)		(365)
Consolidated Interest Expense	$	14,295	$	14,023	$	13,143

Income Taxes:
Regulated	$	3,637	5,653		(146)
Non – Regulated	1,184		1,252		1,187
Consolidated Income Taxes	$	4,821	$	6,905	$	1,041

Net Income:
Regulated	$	40,258	$	41,575	$	29,094
Non – Regulated	2,564		2,776		2,430
Consolidated Net Income	42,822		44,351		31,524

Capital Expenditures:
Regulated	$	96,015	$	74,584	$	90,047
Non – Regulated	339		38		132
Total Capital Expenditures	$	96,354	$	74,622	$	90,179


	(In Thousands)
	As of December 31, 2025		As of December 31, 2024
Assets:
Regulated	$	1,377,391	$	1,264,472
Non – Regulated	9,076		7,671
Total Reportable Segments	1,386,466		1,272,143
Inter-segment Elimination	(20,730)		(16,969)
Consolidated Assets	$	1,365,737	$	1,255,174

Income Taxes - Schedule of Income Tax Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
$
Earnings from continuing operations, before income tax expense	$ 47,643	$ 51,256	$ 32,565
U.S Federal Statutory Tax Rate	10,005	10,764	6,839
State Taxes, Net of Federal Income Tax Effect	1,271	1,270	1,117
Nontaxable or Nondeductible Items
Utility Plant Related	(726)	(659)	(1,495)
Tangible Property Repairs	(5,792)	(4,535)	(5,475)
Other Adjustments	63	65	55
Total Income Tax Expense	$ 4,821	$ 6,905	$ 1,041
%
U.S Federal Statutory Tax Rate	21.00%
State Taxes, Net of Federal Income Tax Effect	2.70%
Nontaxable or Nondeductible Items
Utility Plant Related	(1.50%)
Tangible Property Repairs	(12.20%)
Other Adjustments	0.10%
Total Income Tax Expense	10.10%	13.50%	3.20%

CONSOLIDATED STATEMENTS OF CASH FLOWS (Parentheticals) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Statement of Cash Flows [Abstract]
AFUDC-Debt utility plant expenditures	$ 640	$ 511	$ 975

CONSOLIDATED STATEMENTS OF CAPITAL STOCK AND LONG-TERM DEBT (Parentheticals) - $ / shares shares in Thousands	Dec. 31, 2025	Dec. 31, 2024
Common stock authorized (in shares)	40,000	40,000
Common stock outstanding (in shares)	18,521	17,887
Common stock issued (in shares)	18,521	17,887
Cumulative preferred stock, shares authorized (in shares)	120	120
Cumulative preferred stock, Nonredeemable shares outstanding (in shares)	13	16
Cumulative preferred stock, Nonredeemable shares issued (in shares)	13	16
Cumulative preferred stock, price (in dollars per share)	$ 7.00	$ 7.00
FMBs \| Minimum
Interest rate	0.00%
FMBs \| Maximum
Interest rate	5.99%
Amortizing Secured Notes \| Minimum
Interest rate	3.94%
Amortizing Secured Notes \| Maximum
Interest rate	7.05%
State Revolving Trust Notes \| Minimum
Interest rate	0.00%
State Revolving Trust Notes \| Maximum
Interest rate	4.03%
Convertible Preferred Stock $7.00 Series
Cumulative preferred stock, Nonredeemable shares outstanding (in shares)	2	5
Cumulative preferred stock, Nonredeemable shares issued (in shares)	2	5
Cumulative preferred stock, price (in dollars per share)	$ 7.00
Nonredeemable Preferred Stock $7.00 Series
Cumulative preferred stock, Nonredeemable shares outstanding (in shares)	1	1
Cumulative preferred stock, Nonredeemable shares issued (in shares)	1	1
Cumulative preferred stock, price (in dollars per share)	$ 7.00	$ 7.00
Nonredeemable Preferred Stock $4.75 Series
Cumulative preferred stock, Nonredeemable shares outstanding (in shares)	10	10
Cumulative preferred stock, Nonredeemable shares issued (in shares)	10	10
Cumulative preferred stock, price (in dollars per share)	$ 4.75	$ 4.75

CONSOLIDATED STATEMENTS OF INCOME - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Income Statement [Abstract]
Operating Revenues	$ 194,694	$ 191,877	$ 166,274
Operating Expenses:
Operations and Maintenance	91,291	92,363	83,113
Depreciation	27,113	24,430	25,194
Other Taxes	21,914	21,874	18,744
Total Operating Expenses	140,318	138,667	127,051
Operating Income	54,376	53,210	39,223
Other Income:
Allowance for Funds Used During Construction	1,618	1,254	2,433
Other Income, net	5,944	10,815	4,052
Total Other Income, net	7,562	12,069	6,485
Interest Charges	14,295	14,023	13,143
Income before Income Taxes	47,643	51,256	32,565
Income Taxes	4,821	6,905	1,041
Net Income	42,822	44,351	31,524
Preferred Stock Dividend Requirements	76	112	120
Earnings Applicable to Common Stock, Basic	42,746	44,239	31,404
Earnings Applicable to Common Stock, Diluted	$ 42,746	$ 44,239	$ 31,404
Earnings per share of Common Stock:
Basic (in dollars per share)	$ 2.36	$ 2.48	$ 1.77
Diluted (in dollars per share)	$ 2.36	$ 2.47	$ 1.76
Common Shares Outstanding:
Basic (in shares)	18,096	17,842	17,732
Diluted (in shares)	18,137	17,946	17,847

Employee Benefit Plans - Schedule of Discount and Compensation Rates (Details)	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Pension Plan
Expected Return on Plan Assets for:
Benefit Cost	7.00%	7.00%	7.00%
Discount Rate for:
Benefit Obligation	5.39%	5.47%	4.79%
Benefit Cost	5.47%	4.79%	4.98%
Compensation Increase for:
Benefit Obligation	3.00%	3.00%	3.00%
Benefit Cost	3.00%	3.00%	3.00%
Other Benefits Plan
Expected Return on Plan Assets for:
Benefit Cost	7.00%	7.00%	7.00%
Discount Rate for:
Benefit Obligation	5.49%	5.49%	4.79%
Benefit Cost	5.49%	4.79%	4.98%
Compensation Increase for:
Benefit Obligation	3.00%	3.00%	3.00%
Benefit Cost	3.00%	3.00%	3.00%

Insider Trading Arrangements	3 Months Ended
Insider Trading Arrangements	Dec. 31, 2025
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false

Commitments and Contingent Liabilities - Schedule of Future Minimum Operating Lease Commitments (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Commitments and Contingencies Disclosure [Abstract]
2026	$ 800
2027	900
2028	900
2029	900
2030	0
Total Lease Payments	3,500
Imputed Interest	(1,100)
Present Value of Lease Payments	$ 2,400
Operating Lease, Liability, Statement of Financial Position [Extensible Enumeration]	Present Value of Lease Payments
Less Current Portion	$ (600)
Non-Current Lease Liability	$ 1,838	$ 2,432

Employee Benefit Plans - Schedule of Table Presents Awarded but not Yet Vested Share (Details) - Restricted Stock Units - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Share-Based Compensation Arrangement by Share-Based Payment Award, Non-Option Equity Instruments, Outstanding [Roll Forward]
Outstanding at January 1, 2022 (in shares)	35	74	77	83
Unearned Compensation, Outstanding at January 1, 2022	$ 906	$ 1,043	$ 1,732	$ 1,931
Shares, Granted (in shares)	24	19	15	11
Unearned Compensation, Granted	$ 1,540	$ 1,003	$ 1,165	$ 1,151
Weighted Average Granted Price, Granted (in dollars per share)	$ 64.10	$ 52.50	$ 77.63	$ 105.17
Shares, Vested (in shares)	(17)	(58)	(18)	(17)
Unearned Compensation, Vested		$ 0	$ 0
Shares, Amortization of Compensation expense (in shares)	0	0	0	0
Unearned Compensation, Amortization of Compensation expense	$ (905)	$ (1,140)	$ (1,854)	$ (1,350)
Outstanding at December 31 , 2025 (in shares)	42	35	74	77
Unearned Compensation, Outstanding at December 31 , 2024	$ 1,541	$ 906	$ 1,043	$ 1,732

Organization, Summary of Significant Accounting Policies and Recent Developments (Policies)

12 Months Ended

Dec. 31, 2025

Accounting Policies [Abstract]

Organization

Organization - Middlesex Water Company (Middlesex or the Company) is the parent company and sole shareholder of Tidewater Utilities, Inc. (Tidewater), Pinelands Water Company (Pinelands Water) and Pinelands Wastewater Company (Pinelands Wastewater) (collectively, Pinelands), Utility Service Affiliates, Inc. (USA), Utility Service Affiliates (Perth Amboy) Inc. (USA-PA) and Twin Lakes Utilities, Inc. (Twin Lakes). Southern Shores Water Company, LLC (Southern Shores) and White Marsh Environmental Systems, Inc. (White Marsh) are wholly-owned subsidiaries of Tidewater. The terms “we,” “our,” and “us” collectively refer to Middlesex and its subsidiaries,

Principles of Consolidation

Principles of Consolidation – The financial statements for Middlesex are reported on a consolidated basis. All significant intercompany accounts and transactions have been eliminated. Other financial investments in which the Company holds a 50% or less voting interest, has significant influence and cannot exercise control over the operation and policies of the investments are accounted for under the equity method of accounting. Under the equity method of accounting, the Company records its investment interests in Non-Utility Assets and its percentage share of the earnings or losses of the investees in Other Income.

System of Accounts

System of Accounts – The Company’s regulated utilities maintain their accounts in accordance with the Uniform System of Accounts prescribed by the NJBPU and DEPSC.

Regulatory Accounting

Regulatory Accounting - We maintain our books and records in accordance with accounting principles generally accepted in the United States of America (GAAP). Middlesex and certain of its subsidiaries, which account for 94% of Operating Revenues and 99% of Total Assets, are subject to regulation in the state in which they operate. Those companies are required to maintain their accounts in accordance with regulatory authorities’ rules and guidelines, which may differ from other authoritative accounting pronouncements. In those instances, the Company follows the guidance provided in Accounting Standards Codification (ASC) 980, Regulated Operations.

Retirement Benefit Plans

Retirement Benefit Plans - We maintain a noncontributory defined benefit pension plan (Pension Plan), which covers all active employees who were hired prior to April 1, 2007, as well as a defined contribution plan in which all employees are eligible to participate. In addition, the Company maintains an unfunded supplemental plan for certain of its executive officers. The Company has a retirement benefit plan other than pensions (Other Benefits Plan) for substantially all of its retired employees. Employees hired after March 31, 2007 are not eligible to participate in this plan. Coverage includes healthcare and life insurance.

Utility Plant

Utility Plant – Utility Plant is stated at original cost as defined for regulatory purposes. Property accounts are charged with the cost of betterments and major replacements of property. Cost includes direct material, labor and indirect charges for pension benefits and payroll taxes. The cost of labor, materials, supervision and other expenses incurred in making repairs and maintenance of the properties is charged to the appropriate expense accounts. At December 31, 2025, there was

no event or change in circumstance that would indicate that the carrying amount of any long-lived asset was not recoverable.

Depreciation

Depreciation – Depreciation is computed by each regulated subsidiary of the Company utilizing a rate approved by the applicable regulatory authority. The accumulated provision for depreciation is charged with the cost of property retired, less salvage. The following table sets forth the range of depreciation rates for the major utility plant categories used to calculate depreciation for the years ended December 31, 2025, 2024, and 2023. These rates have been approved by the NJBPU or DEPSC:


Source of Supply	1.15% - 3.44%	Transmission and Distribution (T&D):
Pumping	2.00% - 5.39%	T&D – Mains	1.10% - 3.13%
Water Treatment	1.65% - 7.09%	T&D – Services	2.12% - 3.16%
General Plant	2.08% - 17.84%	T&D – Other	1.61% - 4.63%
Wastewater Collection	1.42% - 1.81%

Non-regulated fixed assets consist primarily of office buildings, furniture and fixtures, and transportation equipment.

Advances for Construction

Advances for Construction– Cash advances are provided to the Company by customers, real estate developers and builders in order to extend utility service to their properties. These transactions are recorded as Advances for Construction (CAC). Contractual refunds of CAC in the form of cash are made by the Company and are based on either additional operating revenues generated from new customers or as new customers are connected to the respective system. After all refunds are made and/or contract terms have expired, any remaining balance is transferred to Contributions in Aid of Construction (CIAC). For the twelve months ended December 31, 2025, the Company refunded $0.5 million of CAC.

CIAC – CIAC include direct non-refundable contributions of utility plant and/or cash and the portion of Advances for Construction that becomes non-refundable.

In accordance with regulatory requirements, Advances for Construction and CIAC are not depreciated. In addition, these amounts reduce the investment base for purposes of setting rates.

Allowance for Funds Used During Construction (AFUDC)

Allowance for Funds Used During Construction (AFUDC) - Middlesex and its regulated subsidiaries capitalize AFUDC, which represents the cost of financing projects during construction. AFUDC is added to the construction costs of individual projects exceeding specific cost and construction period thresholds established for each company and then depreciated with the utility plant direct costs over the underlying assets’ estimated useful life. AFUDC is calculated using each company’s weighted cost of debt and equity as approved in their most recent respective regulatory rate order. The AFUDC rates for the years ended December 31, 2025, 2024 and 2023 for Middlesex and Tidewater are as follows:


	2025		2024		2023
Middlesex	6.64	%	6.64	%	6.35	%
Tidewater	7.04	%	7.92	%	7.92	%

Accounts Receivable

Accounts Receivable – We record bad debt expense based on a variety of factors such as our customers’ payment history, current economic conditions and trending reasonable and supportable forecasts on expected collectability of accounts receivable.

Revenues

Revenues - The Company’s revenues are primarily generated from regulated tariff-based water and wastewater utility services and non-regulated operation and maintenance contracts for services on water and wastewater systems owned by others. Revenue from contracts with customers is recognized when control of a promised good or service is transferred to customers at an amount that reflects the consideration to which the Company expects to be entitled in exchange for those goods and services.

Substantially all of the amounts included in operating revenues and accounts receivable are from contracts with customers.

The Company’s contracts do not contain any significant financing components.

Unamortized Debt Expense and Premiums on Long-Term Debt

Unamortized Debt Expense and Premiums on Long-Term Debt - Unamortized Debt Expense and Premiums on Long-Term Debt, included on the consolidated balance sheet in long-term debt, are amortized over the lives of the related debt.

Income Taxes

Income Taxes - Middlesex files a consolidated federal income tax return for the Company. Certain income and expense items are accounted for in different time periods for financial reporting than for income tax reporting purposes. The determination of our provision for income taxes requires the use of estimates and the interpretation and application of tax laws. Judgment is required in assessing the deductibility and recoverability of certain tax benefits. We use the asset and liability method to determine and record deferred tax assets and liabilities, representing future tax benefits and taxes payable, which result from the differences in basis recorded in GAAP financial statements and amounts recorded in the income tax returns. The deferred tax assets and liabilities are recorded utilizing the statutorily enacted tax rates expected to be in effect at the time the assets are realized and/or the liabilities settled. An offsetting valuation allowance is recorded when it is more likely than not that some or all of the deferred income tax assets won’t be realized. Any significant changes to the estimates and judgments with respect to the interpretations, timing or deductibility could result in a material change to earnings and cash flows. Investment tax credits have been deferred and are amortized over the estimated useful life of the related property. In the event there are interest and penalties associated with income tax adjustments from income tax authority examinations, these amounts will be reported under interest charges and other expense, respectively. For more information on income taxes, see Note 3 – Income Taxes.

Cash and Cash Equivalents

Cash and Cash Equivalents - For purposes of reporting cash flows, the Company considers all highly liquid investments with original maturity dates of three months or less to be cash equivalents. Cash and cash equivalents represent bank balances and money market funds with investments maturing in less than 90 days. Restricted cash includes amounts held in escrow related to the acquisition of a subsidiary currently in receivership by another utility.

Use of Estimates

Use of Estimates - Conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts in the financial statements. Actual results could differ from those estimates.

Recent Accounting Pronouncements

Recent Accounting Pronouncements - The recently issued accounting standards and their impact on the Company as of December 31, 2025 are as follows:

Standard

Description

Date of Adoption

Application

Effect on the
Condensed
Consolidated
Financial Statements

Accounting Standards Update (ASU) 2023-09 “Improvements to Income Tax Disclosures”

The ASU is effective for the Company beginning with its annual financial statements for the year ending December 31, 2025.

Prospective, with retrospective application also permitted.

ASU 2024-03 “Disaggregation of Income Statement Expenses”

The ASU is effective for the Company beginning with its annual financial statements for the year ending December 31, 2027.

Prospective, with retrospective application also permitted.

The Company is currently evaluating the requirements of ASU 2024-03.

ASU 2025-06 "Internal-Use Software"

The ASU is effective for the Company beginning with its annual financial statements for the year ending December 31, 2028.

Prospective, with a modified transition or retrospective application also permitted.

The Company is evaluating the impact of ASU 2025-06 on its Consolidated Financial Statements and the timing of adoption.

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2025

Income Tax Disclosure [Abstract]

Schedule of Reconciliation Of Income Taxes


	($ in Thousands)
	Year Ended December 31, 2025
	$		%
Earnings from continuing operations, before income tax expense	$	47,643

U.S Federal Statutory Tax Rate	10,005		21.0	%
State Taxes, Net of Federal Income Tax Effect (*)	1,271		2.7	%
Nontaxable or Nondeductible Items
Utility Plant Related	(726)		(1.5)	%
Tangible Property Repairs	(5,792)		(12.2)	%
Other Adjustments	63		0.1	%
Total Income Tax Expense	$	4,821	10.1	%

(*) State taxes in Delaware make up the majority (greater than 50 percent) of the tax effect in this category.


	Years Ended December 31,
	2024		2023
Income Tax at Statutory Rate	$	10,764	$	6,839
Tax Effect of:
Utility Plant Related	(659)		(1,495)
Tangible Property Repairs	(4,535)		(5,475)
State Income Taxes-Net	1,270		1,117
Other	65		55
Total Income Tax Expense	$	6,905	$	1,041

Schedule of Paid Income taxes

The Company paid income taxes as follows:


	Year Ended
	December 31, 2025
Federal taxes Paid	$	236

State Taxes Paid-New Jersey	307
State Taxes Paid-Delaware	1,092
State Taxes Paid-Other	4
Total State Taxes Paid	$	1,403

Total Income Taxes Paid	$	1,639


(in thousands)	2025		2024		2023
SUPPLEMENTAL DISCLOSURE OF NON-CASH ACTIVITY:
Utility Plant received as Construction Advances and Contributions	$	9,924	$	8,968	$	7,259
Accrued Payables for Utility Plant	9,901		8,109		10,251
Litigation Settlement Receivable	—		(6,237)		69,872
Litigation Settlement Payable	—		(6,237)		6,237
Conversion of Preferred Stock Into Common Stock	292		449		—

SUPPLEMENTAL DISCLOSURE OF CASH FLOWS INFORMATION:
Cash Paid During the Year for:
Interest	13,459		14,485		12,762
Interest Capitalized	640		511		975
Income Taxes	1,639		3,169		2,962

Schedule of Components of Income Tax Expense (Benefit)

Income tax expense (benefit) is comprised of the following:


	(In Thousands)
	Years Ended December 31,
	2025		2024		2023
Current:
Federal	$	2,971	$	1,554	$	2,952
State	1,292		1,126		1,066
Deferred:
Federal	295		3,802		(3,261)
State	317		482		348
Investment Tax Credits	(54)		(59)		(64)
Total Income Tax Expense	$	4,821	$	6,905	$	1,041

Schedule of Deferred Income Taxes

The components of the net deferred tax liability are as follows:


	(In Thousands)
	December 31,
	2025		2024
Utility Plant Related	$	100,934	$	95,877
Customer Advances	850		(3,525)
Employee Benefits	8,778		7,888
Investment Tax Credits	128		181
Other	(215)		814
Total Accumulated Deferred Income Taxes	$	110,475	$	101,235

Employee Benefit Plans - Schedule of Change in Fair Value of Plan Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024
Pension Plan
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Beginning Balance	$ 98,648	$ 92,346
Actual Return on Plan Assets	9,566	7,976
Employer Contributions	886	2,750
Benefits Paid	(5,079)	(4,424)
Ending Balance	104,021	98,648
Funded Status	14,971	11,147
Other Benefits Plan
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Beginning Balance	53,027	48,352
Actual Return on Plan Assets	7,473	4,675
Employer Contributions	1,102	946
Benefits Paid	(1,102)	(946)
Ending Balance	60,500	53,027
Funded Status	$ 28,474	$ 24,826

- Definition

Amount of contribution received by defined benefit plan from employer which increases plan assets.

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+ Details

- Definition

Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee.

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+ Details

Employee Benefit Plans - Schedule of Fair Value of Plan Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Pension Plan
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments	$ 104,021	$ 98,648	$ 92,346
Pension Plan \| Mutual Funds
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments		31,187
Pension Plan \| Money Market Funds
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments	637	293
Pension Plan \| Government Treasury
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments	21,546
Pension Plan \| Common Equity Securities
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments	32,400	195
Pension Plan \| Corporate Bonds
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments	44,878	42,974
Pension Plan \| Agency/US Debt
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments		19,041
Pension Plan \| Sovereign/Non-US Debt
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments	4,560	4,958
Pension Plan \| Level 1
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments	54,583	98,648
Pension Plan \| Level 1 \| Mutual Funds
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments		31,187
Pension Plan \| Level 1 \| Money Market Funds
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments	637	293
Pension Plan \| Level 1 \| Government Treasury
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments	21,546
Pension Plan \| Level 1 \| Common Equity Securities
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments	32,400	195
Pension Plan \| Level 1 \| Corporate Bonds
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments	0	42,974
Pension Plan \| Level 1 \| Agency/US Debt
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments		19,041
Pension Plan \| Level 1 \| Sovereign/Non-US Debt
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments	0	4,958
Pension Plan \| Level 2
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments	49,438	0
Pension Plan \| Level 2 \| Mutual Funds
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments		0
Pension Plan \| Level 2 \| Money Market Funds
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments	0	0
Pension Plan \| Level 2 \| Government Treasury
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments	0
Pension Plan \| Level 2 \| Common Equity Securities
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments	0	0
Pension Plan \| Level 2 \| Corporate Bonds
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments	44,878	0
Pension Plan \| Level 2 \| Agency/US Debt
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments		0
Pension Plan \| Level 2 \| Sovereign/Non-US Debt
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments	4,560	0
Pension Plan \| Level 3
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments	0	0
Pension Plan \| Level 3 \| Mutual Funds
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments		0
Pension Plan \| Level 3 \| Money Market Funds
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments	0	0
Pension Plan \| Level 3 \| Government Treasury
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments	0
Pension Plan \| Level 3 \| Common Equity Securities
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments	0	0
Pension Plan \| Level 3 \| Corporate Bonds
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments	0	0
Pension Plan \| Level 3 \| Agency/US Debt
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments		0
Pension Plan \| Level 3 \| Sovereign/Non-US Debt
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments	0	0
Other Benefits Plan
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments	60,500	53,027
Other Benefits Plan \| Mutual Funds
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments		34,545
Other Benefits Plan \| Money Market Funds
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments	885	977
Other Benefits Plan \| Cash
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments	317
Other Benefits Plan \| Common Equity Securities
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments	41,150
Other Benefits Plan \| Agency/US Debt
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments	18,148	17,505
Other Benefits Plan \| Level 1
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments	42,352	35,522
Other Benefits Plan \| Level 1 \| Mutual Funds
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments		34,545
Other Benefits Plan \| Level 1 \| Money Market Funds
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments	885	977
Other Benefits Plan \| Level 1 \| Cash
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments	317
Other Benefits Plan \| Level 1 \| Common Equity Securities
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments	41,150
Other Benefits Plan \| Level 1 \| Agency/US Debt
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments	0	0
Other Benefits Plan \| Level 2
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments	18,148	17,505
Other Benefits Plan \| Level 2 \| Mutual Funds
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments		0
Other Benefits Plan \| Level 2 \| Money Market Funds
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments	0	0
Other Benefits Plan \| Level 2 \| Cash
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments	0
Other Benefits Plan \| Level 2 \| Common Equity Securities
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments	0
Other Benefits Plan \| Level 2 \| Agency/US Debt
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments	18,148	17,505
Other Benefits Plan \| Level 3
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments	0	0
Other Benefits Plan \| Level 3 \| Mutual Funds
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments		0
Other Benefits Plan \| Level 3 \| Money Market Funds
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments	0	0
Other Benefits Plan \| Level 3 \| Cash
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments	0
Other Benefits Plan \| Level 3 \| Common Equity Securities
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments	0
Other Benefits Plan \| Level 3 \| Agency/US Debt
Defined Benefit Plan, Plan Assets, Category [Line Items]
Total Investments	$ 0	$ 0

Business Segment Data - Schedule of Segment Transactions (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Revenues:
Operating Revenues	$ 194,694	$ 191,877	$ 166,274
Purchased Water:
Consolidated Purchased Water	7,994	7,497	8,481
Other Operations and Maintenance Expenses:
Consolidated Other Operations and Maintenance Expenses	83,297	84,866	74,632
Other Taxes:
Consolidated Other Taxes	21,914	21,874	18,744
Depreciation:
Consolidated Depreciation	27,113	24,430	25,194
Operating Income:
Consolidated Operating Income	54,376	53,210	39,223
Other Income (Expense), Net:
Consolidated Other Income, Net	7,562	12,069	6,485
Interest Expense:
Consolidated Interest Charges	14,295	14,023	13,143
Income Taxes:
Consolidated Income Taxes	4,821	6,905	1,041
Net Income:
Consolidated Net Income	42,822	44,351	31,524
Capital Expenditures:
Capital Expenditures:	96,354	74,622	90,179
ASSETS
Consolidated Assets	1,365,737	1,255,174
Regulated
Other Taxes:
Consolidated Other Taxes	21,675	21,644	18,504
Non – Regulated
Other Taxes:
Consolidated Other Taxes	239	230	240
Operating Segments
Revenues:
Operating Revenues	195,639	192,911	167,390
Purchased Water:
Consolidated Purchased Water	8,458	8,064	9,144
Other Operations and Maintenance Expenses:
Consolidated Other Operations and Maintenance Expenses	83,778	85,333	75,085
Other Income (Expense), Net:
Consolidated Other Income, Net	8,237	12,476	6,851
Interest Expense:
Consolidated Interest Charges	14,970	14,430	13,508
ASSETS
Consolidated Assets	1,386,466	1,272,143
Operating Segments \| Regulated
Revenues:
Operating Revenues	182,654	179,359	154,617
Purchased Water:
Consolidated Purchased Water	8,458	8,064	9,144
Other Operations and Maintenance Expenses:
Consolidated Other Operations and Maintenance Expenses	75,293	76,483	66,670
Depreciation:
Consolidated Depreciation	26,844	24,173	24,931
Operating Income:
Consolidated Operating Income	50,865	49,462	35,820
Other Income (Expense), Net:
Consolidated Other Income, Net	8,001	12,195	6,637
Interest Expense:
Consolidated Interest Charges	14,970	14,430	13,508
Income Taxes:
Consolidated Income Taxes	3,637	5,653	(146)
Net Income:
Consolidated Net Income	40,258	41,575	29,094
Capital Expenditures:
Capital Expenditures:	96,015	74,584	90,047
ASSETS
Consolidated Assets	1,377,391	1,264,472
Operating Segments \| Non – Regulated
Revenues:
Operating Revenues	12,985	13,552	12,773
Purchased Water:
Consolidated Purchased Water	0	0	0
Other Operations and Maintenance Expenses:
Consolidated Other Operations and Maintenance Expenses	8,485	8,850	8,415
Depreciation:
Consolidated Depreciation	269	257	263
Operating Income:
Consolidated Operating Income	3,511	3,748	3,403
Other Income (Expense), Net:
Consolidated Other Income, Net	236	281	214
Interest Expense:
Consolidated Interest Charges	0	0	0
Income Taxes:
Consolidated Income Taxes	1,184	1,252	1,187
Net Income:
Consolidated Net Income	2,564	2,776	2,430
Capital Expenditures:
Capital Expenditures:	339	38	132
ASSETS
Consolidated Assets	9,076	7,671
Inter-segment Elimination
Revenues:
Operating Revenues	(945)	(1,034)	(1,116)
Purchased Water:
Consolidated Purchased Water	(464)	(567)	(663)
Other Operations and Maintenance Expenses:
Consolidated Other Operations and Maintenance Expenses	(481)	(467)	(453)
Other Income (Expense), Net:
Consolidated Other Income, Net	(675)	(407)	(366)
Interest Expense:
Consolidated Interest Charges	(675)	(407)	$ (365)
ASSETS
Consolidated Assets	$ (20,730)	$ (16,969)

Commitments and Contingent Liabilities - Narrative (Details) gal in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2025 USD ($) gal	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
Loss Contingencies [Line Items]
Estimated incremental borrowing rate	4.03%
Expenditures for operating leases \| $	$ 0.8	$ 0.8	$ 0.8
New Jersey Water Supply Authority Untreated Water Agreement
Loss Contingencies [Line Items]
Average purchase of gallons a day under agreement (in mgd)	27.0
New Jersey Water Supply Authority Untreated Water Agreement \| Maximum
Loss Contingencies [Line Items]
Average purchase of gallons a day under agreement (in mgd)	47.0
New Jersey Board Of Public Utilities Treated Water Agreement \| Minimum
Loss Contingencies [Line Items]
Average purchase of gallons a day under agreement (in mgd)	3.0
Treated Water
Loss Contingencies [Line Items]
Average purchase of gallons	75.0
Construction Agreement
Loss Contingencies [Line Items]
Estimated future expenditure obligation \| $	$ 21.0

Commitments and Contingent Liabilities (Tables)

12 Months Ended

Dec. 31, 2025

Commitments and Contingencies Disclosure [Abstract]

Schedule of Purchased Water Costs

Purchased water costs are shown below:


	(In Millions)
	Years Ended December 31,
	2025		2024		2023
Untreated	$	3.6	$	3.5	$	3.2
Treated	4.4		4.0		5.3
Total Costs	$	8.0	$	7.5	$	8.5

Schedule of Operating Lease ROU Assets

Information related to operating lease ROU assets is as follows:


	(In Millions)
	December 31,
	2025		2024
ROU Asset at Lease Inception	$	7.3	$	7.3
Accumulated Amortization	(5.3)		(4.7)
Current ROU Asset	$	2.0	$	2.6

Schedule of Future Minimum Operating Lease Commitments

The Company’s future minimum operating lease commitments as of December 31, 2025 are as follows:


	(In Millions)
	December 31, 2025
2026	$	0.8
2027	0.9
2028	0.9
2029	0.9
2030	—
Total Lease Payments	$	3.5
Imputed Interest	(1.1)
Present Value of Lease Payments	2.4
Less Current Portion*	(0.6)
Non-Current Lease Liability	$	1.8

*Included in Other Current Liabilities

Capitalization - Schedule of Carrying Amount and Fair Value of the Bonds (Details) - Loans Payable - FMBs - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
FMBs	$ 126,172	$ 129,602
Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
FMBs	$ 120,430	$ 125,067

- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482907/825-10-50-10

Reference 9: http://www.xbrl.org/2003/role/exampleRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 12
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482881/825-10-55-12

Reference 10: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

+ Details

Employee Benefit Plans - Schedule of Employee Retirement Benefit Plans (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Pension Plan
Defined Benefit Plan, Roll Forwards [Abstract]
Beginning Balance	$ 87,501	$ 91,853
Service Cost	967	1,270	$ 1,551
Interest Cost	4,635	4,280	4,270
Actuarial (Gain) Loss	1,026	(5,478)
Benefits Paid	(5,079)	(4,424)
Ending Balance	89,050	87,501	91,853
Other Benefits Plan
Defined Benefit Plan, Roll Forwards [Abstract]
Beginning Balance	28,201	28,000
Service Cost	340	320	391
Interest Cost	1,719	1,313	1,608
Actuarial (Gain) Loss	2,867	(486)
Benefits Paid	(1,102)	(946)
Ending Balance	$ 32,025	$ 28,201	$ 28,000

CONSOLIDATED STATEMENTS OF COMMON STOCKHOLDERS' EQUITY (Parentheticals) - $ / shares	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Statement of Stockholders' Equity [Abstract]
Cash dividends on Common Stock (in dollars per share)	$ 1.3800	$ 1.3150	$ 1.2625
Cumulative preferred stock, price (in dollars per share)	$ 7.00	$ 7.00	$ 7.00

Employee Benefit Plans - Schedule of Regulatory Assets into Net Periodic Benefit Cost (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2025 USD ($)
Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Actuarial Loss (Gain)	$ 74
Other Benefits Plan
Defined Benefit Plan Disclosure [Line Items]
Actuarial Loss (Gain)	$ (1,071)

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

+ Details

Short-term Borrowings

12 Months Ended

Dec. 31, 2025

Short-Term Debt [Abstract]

Short-term Borrowings

Information regarding the Company’s short-term borrowings for the years ended December 31, 2025 and 2024 is summarized below:


	($ In Millions)
	2025			2024
Average Amount Outstanding	$	42.1		$	38.7
Weighted Average Interest Rate	5.42		%	6.33		%
Notes Payable at Year-End	$	28.3		$	23.0
Weighted Average Interest Rate at Year-End	5.03		%	5.63		%

As of December 31, 2025, the Company maintains bank lines of credit aggregating $148.0 million.


	(In Millions)
	As of December 31, 2025							Line of Credit Expiration Date
	Outstanding		Available		Maximum		Credit Type
Bank of America	$	—	$	60.0	$	60.0	Uncommitted	July 31, 2026
PNC Bank	9.3		58.7		68.0		Committed	January 31, 2027
CoBank, ACB (CoBank)	19.0		1.0		20.0		Committed	May 20, 2028
	$	28.3	$	119.7	$	148.0

The maturity dates for the Notes Payable as of December 31, 2025 are all three months or less extendable at the discretion of the Company.

In July 2025, Tidewater increased the maximum borrowing amount under its line of credit with CoBank, ACB (CoBank) to $20.0 million and extended the expiration date to May 2028.

In September 2025, the Company amended its line of credit with Bank of America and extended the expiration date to July 2026.

In February 2026, the Company amended its line of credit with PNC Bank. Under the terms of the amendment, the expiration date was extended to January 31, 2029 and the maximum borrowing amount was increased to $100 million.

The interest rates are set for borrowings under the Bank of America and PNC Bank lines of credit using the Secured Overnight Financing Rate (SOFR) and then adding a specific financial institution credit spread. The interest rate for borrowings under the CoBank line of credit are set weekly using CoBank’s internal cost of funds index that is similar to the SOFR and adding a credit spread. There is no requirement for a compensating balance under any of the established lines of credit.